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Black-white differences in physiology can tell a lot about how the two groups have evolved over time. On traits like resting metabolic rate (RMR), basal metabolic rate (BMR), adiposity, heart rate, Vo2 max, etc. These differences in physiological variables between groups, then, explain part of the reason why there are different outcomes in terms of life quality/mortality between the two groups.
Right away, by looking at the average black and average white, you can see that there are differences in somatype. So if there are differences in somatype, then there must be differences in physiological variables, and so, this may be a part of the cause of, say, differing obesity rates between black and white women (Albu et al, 1997) and even PCOS (Wang and Alvero, 2013).
Resting metabolic rate
Resting metabolic rate is your body’s metabolism at rest, and is the largest component of the daily energy budget in modern human societies (Speakman and Selman, 2003). So if two groups, on average, differ in RMR, then one with the lower RMR may have a higher risk of obesity than the group with the higher RMR. And this is what we see.
Black women do, without a shadow of a doubt, have a lower BMR, lower PAEE (physical activity energy expenditure) and TDEE (total daily expenditure) (Gannon, DiPietro, and Poehlman, 2000). Knowing this, then it is not surprising to learn that black women are also the most obese demographic in the United States. This could partly explain why black women have such a hard time losing weight. Metabolic differences between ethnic groups in America—despite living in similar environments—show that a genetic component is responsible for this.
There are even predictors of obesity in post-menopausal black and white women (Nicklas et al, 1999). They controlled for age, body weight and body composition (variables that would influence the results—no one tell me that “They shouldn’t have controlled for those because it’s a racial confound!”) and found that despite having a similar waist-to-hip ratio (WHR) and subcutaneous fat area, black women had lower visceral fat than white women, while fasting glucose, insulin levels, and resting blood pressure did not differ between the groups. White women also had a higher Vo2 max, which remained when lean mass was controlled for. White women could also oxidize fat at a higher rate than black women (15.4 g/day, which is 17% higher than black women). When this is expressed as percent of total kcal burned in a resting state, white women burned more fat than black women (50% vs 43%). I will cover the cause for this later in the article (one physiologic variable is a large cause of these differences).
We even see this in black American men with more African ancestry—they’re less likely to be obese (Klimentidis et al 2016). This, too, goes back to metabolic rate. Black American men have lower levels of body fat than white men (Vickery et al, 1988; Wagner and Heyward, 2000). All in all, there are specific genetic variants and physiologic effects, which cause West African men to have lower central (abdominal) adiposity than European men and black women who live in the same environment as black men—implying that genetic and physiologic differences between the sexes are the cause for this disparity. Whatever the case may be, it’s interesting and more studies need to be taken out so we can see how whatever gene variants are *identified* as protecting against central adiposity work in concert with the system to produce the protective effect. Black American men have lower body fat, therefore they would have, in theory, a higher metabolic rate and be less likely to be obese—while black women have the reverse compared to white women—a lower metabolic rate.
Skeletal muscle fiber
Skeletal muscle fibers are the how and why of black domination in explosive sports. This is something I’ve covered in depth. Type II fibers contract faster than type I. This has important implications for certain diseases that black men are more susceptible to. Though the continuous contraction of the fibers during physical activity leads to a higher disease susceptibility in black men—but not white men (Tanner et al, 2001). If you’re aware of fiber type differences between the races (Ama et al, 1986; Entine, 2000; Caeser and Henry, 2015); though see Kerr (2010’s) article The Myth of Racial Superiority in Sports for another view. That will be covered here in the future.
Nevertheless, fiber typing explains racial differences in sports, with somatype being another important variable in explaining racial disparities in sports. Two main variables that work in concert are the somatype (pretty much body measurements, length) and the fiber type. This explains why blacks dominate baseball and football; this explains why ‘white men can’t jump and black men can’t swim’. Physiological variables—not only ‘motivation’ or whatever else people who deny these innate differences say—largely explain why there are huge disparities in these sports. Physiology is important to our understanding of how and why certain groups dominate certain sports.
This is further compounded by differing African ethnies excelling in different running sports depending on where their ancestors evolved. Kenyans have an abundance of type I fibers whereas West Africans have an abundance of type II fibers. (Genetically speaking, ‘Jamaicans’ don’t exist; genetic testing shows them to come from a few different West African countries.) Lower body symmetry—knees and ankles—show that they’re more symmetrical than age-matched controls (Trivers et al, 2014). This also goes to show that you can’t teach speed (Lombardo and Deander, 2014). Though, of course, training and the will to want to do your best matter as well—you just cannot excel in these competitions without first and foremost having the right physiologic and genetic make-up.
Further, although it’s only one gene variant, ACTN3 and ACE explain a substantial percentage of sprint time variance, which could be the difference between breaking a world record and making a final (Papadimitriou et al, 2016). So, clearly, certain genetic variants matter more than others—and the two best studied are ACTN3 and ACE. Some authors, though, may deny the contribution of ACTN3 to elite athletic performance—like one researcher who has written numerous papers on ACTN3, Daniel MacArthur. However, elite sprinters are more likely to carry the RR ACTN3 genotype compared to the XX ACTN3 genotype, and the RR ACTN3 genotype—when combined with type II fibers and morphology—lead to increased athletic performance (Broos et al, 2016). It’s also worth noting that 2 percent of Jamaicans carry the XX ACTN3 genotype (Scott et al, 2010), so this is another well-studied variable that lends to superior running performance in Jamaicans.
In regards to Kenyans, of course when you are talking about genetic reasons for performance, some people don’t like it. Some may say that certain countries dominate in X, and that for instance, North Africa is starting to churn out elite athletes, should we begin looking for genetic advantages that they possess (Hamilton, 2000)? Though people like Hamilton are a minority view in this field, I have read a few papers that there is no evidence that Kenyans possess a pulmonary system that infers a physiologic advantage over whites (Larsen and Sheel, 2015).
People like these three authors, however, are in the minority here and there is a robust amount of research that attests to East African running dominance being genetic/physiologic in nature—though you can’t discredit SES and other motivating variables (Tucker, Onywera, and Santos-Concejero, 2015). Of course, a complex interaction between SES, genes, and environment are the cause of the success of the Kalenjin people of Kenya, because they live and train in such high altitudes (Larsen, 2003), though the venerable Bengt Saltin states that the higher Vo2 max in Kenyan boys is due to higher physical activity during childhood (Saltin et al, 1995).
The last variable I will focus on (I will cover more in the future) is blood pressure. It’s well known that blacks have higher blood pressure than whites—with black women having a higher BP than all groups—which then leads to other health implications. Some reasons for the cause are high sodium intake in blacks (Jones and Hall, 2006); salt (Lackland, 2014; blacks had a similar sensitivity than whites, but had a higher blood pressure increase); while race and ethnicity was a single independent predictor of hypertension (Holmes et al, 2013). Put simply, when it comes to BP, ethnicity matters (Lane and Lip, 2001).
While genetic factors are important in showing how and why certain ethnies have higher BP than others, social factors are arguably more important (Williams, 1992). He cites stress, socioecologic stress, social support, coping patterns, health behavior, sodium, calcium, and potassium consumption, alcohol consumption, and obesity. SES factors, of course, lead to higher rates of obesity (Sobal and Stunkard, 1989; Franklin et al, 2015). So, of course, environmental/social factors have an effect on BP—no matter if the discrimination or whatnot is imagined by the one who is supposedly discriminated against, this still causes physiologic changes in the body which then lead to higher rates of BP in certain populations.
Poverty does affect a whole slew of variables, but what I’m worried about here is its effect on blood pressure. People who are in poverty can only afford certain foods, which would then cause certain physiologic variables to increase, exacerbating the problem (Gupta, de Wit, and McKeown, 2007). Whereas diets high in protein predicted lower BP in adults (Beundia et al, 2015). So this is good evidence that the diets of blacks in America do increase BP, since they eat high amounts of salt, low protein and high carb diets.
Still, others argue that differences in BP between blacks and whites may not be explained by ancestry, but by differences in education, rather than genetic factors (Non, Gravlee, and Mulligan, 2012). Their study suggests that educating black Americans on the dangers and preventative measures of high BP will reduce BP disparities between the races. This is in-line with Williams (1992) in that the social environment is the cause for the higher rates of BP. One hypothesis explored to explain why this effect with education was greater in blacks than whites was that BP-related factors, such as stress, poverty and racial discrimination (remember, even if no racial discrimination occurs, any so-called discrimination is in the eye of the beholder so that will contribute to a rise in physiologic variables) and maybe social isolation may be causes for this phenomenon. Future studies also must show how higher education causes lower BP, or if it only serves as other markers for the social environment. Nevertheless, this is an important study in our understanding of how and why the races differ in BP and it will go far to increase our understanding of this malady.
This is not an exhaustive list—I could continue writing about other variables—but these three are some of the most important as they are a cause for higher mortality rates in America. Understanding the hows and whys of these variables will have us better equipped to help those who suffer from diseases brought on by these differences in physiological factors.
The cause for some of these physiologic differences come down to evolution, but still others may come down to the immediate obesogenic environment (Lake and Townshend, 2006) which is compounded by lower SES. Since high carbs diets increase BP, this explains part of the reason why blacks have higher BP, along with social and genetic factors. Muscle fiber typing is set by the second trimester, and no change is seen after age 6 (Bell, 1980). Resting metabolic rate gap differences between black and white women can be closed, but not completely, if black women were to engage in exercise that use their higher amounts of type II muscle fibers (Tanner et al, 2001). This research is important to understand differences in racial mortality; because when we understand them then we can begin to theorize on how and why we see these disparities.
Physiologic differences between the races are interesting, they’re easily measurable and they explain both disparities in sports and mortality by different diseases. Once we study these variables more, we will be better able to help people with these variables—race be dammed. Race is a predictor here, only because race is correlated with other variables that lead to negative health outcomes. So once we understand how and why these differences occur, then we can help others with similar problems—no matter their race.
Last month I argued that there was more to weight loss than CI/CO. One of the culprits is a virus called Ad-36. Obese people are more likely to have Ad-36 antibodies in comparison to lean people, which implies that they have/had the virus and could be a part of the underlying cause of obesity. However, a paper was recently published that your stool can predict whether or not you can lose weight. This is due to how certain bacteria in the gut respond to different macronutrients ingested into the body.
ScienceDaily published an article a few days ago titled Your stools reveal whether you can lose weight. In the article, they describe the diets of the cohort, which followed 31 people, some followed the New Nordic Diet (NND), while others followed the Average Danish Diet (ADD) (Hjorth et al, 2017; I can’t find this study!! I’ll definitely edit this article after I read the full paper when it is available). So 31 people ate the NDD for 26 weeks, and lost 3.5 kg (7.72 pounds for those of us who use freedom numbers) while those who ate the ADD lost an average of 1.7 kg (3.75 pounds for those of us who use freedom numbers). So there was a 1.8 kg difference in pounds lost between the two diets. Why?
Here’s the thing: when people were divided by their microbiota, those who had a higher proportion of Prevotella to Bacteriodoites lost 3.5 more kg (7.72 pounds) in 26 weeks when they ate the NND in comparison to the ADD. Those who had a lower proportion of Prevotella to Bacteriodoites lost no additional weight on the NND. Overall, they say, about 50 percent of the population would benefit from the NND, while the rest of the population should diet and exercise until new measures are found.
The New Danish Diet is composed of grains, fruits, and vegetables. The diet worked for one-half of the population, but not for the other. The researchers state that people should try other diets and to exercise for weight loss while they study other measures. This is important to note: the same diet did not induce weight loss in a population; the culprit here is the individual microbiome.
Now that those Bacteroidotes have come up again, this quote from Allana Collen’s 2014 book 10% Human: How Your Body’s Microbes Hold the Key to Health and Happiness:
But before we get too excited about the potential for a cure for obesity, we need to know how it all works. What are these microbes doing that make us fat? Just as before, the microbiotas in Turnbaugh’s obese mice contained more Firmicutes and fewer Bacteroidetes, and they somehow seemed to enable the mice to extract more energy from their food. This detail undermines one of the core tenets of the obesity equation. Counting ‘calories-in’ is not as simple as keeping track of what a person eats. More accurately, it is the energy content of what a person absorbs. Turnbaugh calculated that the mice with the obese microbiota were collecting 2 per cent more calories from their food. For every 100 calories the lean mice extracted, the obese mice squeezed out 102.
Not much, perhaps, but over the course of a year or more, it adds up. Let’s take a woman of average height. 5 foot 4 inches, who weights 62 kg (9st 11 lb) and a healthy Body Mass Index (BMI: weight (kg) /(height (m)^2) of 23.5. She consumes 2000 calories per day, but with an ‘obese’ microbiota, her extra 2 per cent calorie extraction adds 40 more calories each day. Without expending extra energy, those further 40 calories per day should translate, in theory at least, to a 1.9 kg weight gain over a year. In ten years, that’s 19 kg, taking her weight to 81 kg (12 st 11 lb) and her BMI to an obese 30.7. All because of just 2 percent extra calories extracted from her food by her gut bacteria.
This corresponds with the NND/ADD study on weight loss… This proves that there is more than the simplistic CI/CO to weight loss, and that an individual’s microbiome/physiology definitely does matter in regards to weight loss. Clearly, to understand the population-wide problem of obesity we must understand the intricate relationship between the microbiome/brain/gut/body relationship and how it interacts with what we eat. Because evidence is mounting that the individual’s microbiome houses the key to weight loss/gain.
Exercise does not induce weight loss. A brand new RCT (randomized controlled trial) showed that in a cohort of children who were made to do HIIT (high-intensity interval training) did show better cardiorespiratory fitness, but there were no concomitant reductions in adiposity and bio blood markers (Dias et al, 2017). What this tells me is that people should exercise for health and that ‘high’ that comes along with it; if people exercise for weight loss they will be highly disappointed. Note, I am NOT saying to not exericse, I’m only saying to not have any unrealistic expectations that cardio will induce it, it won’t!
Bjornara et al (2016) showed that, when the NND was compared to the ADD, there was better adherence to the NND when compared to the ADD. Poulskin et al (2015) showed that the NND provided higher satisfaction, and body weight reduction with higher compliance with the NND and with physical activity (I disagree there, see above).
This study is important for our understanding of weight loss for the population as a whole. More recent evidence has shown that our microbiome and body clock work together to ‘pack on the pounds‘. This recent study found that the microbiome “regulate[s] lipid (fat) uptake and storage by hacking into and changing the function of the circadian clocks in the cells that line the gut.” The individual microbiome could induce weight gain, especially when they consume a Western diet, which of course is full of fat and sugar. One of the most important things they noticed is that mice without a microbiome fared much better on a high-fat diet.
The microbiome ‘talks’ to the gut lining. Germ-free mice were genetically unable to make NFIL3 in the cell lining of the gut. So germ-free mice lack a microbiome and lower than average production of NFIL3, meaning they take up and store fewer lipids than those with a microbiome.
So the main point about this study is the circadian rhythm. The body’s circadian clock recognizes the day/night system, which of course are linked to feeding times, which turn the body’s metabolism on and off. Cells are not directly exposed to light, but they capture light cues from visual and nervous systems, which then regulates gene expression. The gut’s circadian clock then regulates the expression of NFIL3 and the lipid metabolic machinery which is controlled NFIL3. So this study shows how the microbiome interacts with and impacts metabolism. This could also, as the authors state, explain how and why people who work nights and have shift-work disorder and the concurrent metabolic syndromes that come along with it.
In regards to the microbiome and weight loss, it is poorly understood at the moment (Conlon and Bird, 2015), though a recent systematic review showed that restrictive diets and bariatric surgery “reduce microbial abundance and promote changes in microbial composition that could have long-term detrimental effects on the colon.” They further state that “prebiotics might restore a healthy microbiome and reduce body fat“(Segenfrado et al, 2017). Wolf and Lorenz (2012) show that using “good” probiotic bacteria may induce changes in the obese phenotype. Bik (2015) states that learning more about the microbiome, dysbiosis (Carding et al, 2015), and how the microbiome interacts with our metabolism, brain, and physiology, then we can better treat those with obesity due to the dysbiosis of the microbiome. Clark et al (2012) show how the mechanisms behind the microbiota and obesity.
Weight loss is, clearly, more than CI/CO, and once we understand other mechanisms of weight loss/gain/regulation then we can better treat people with these metabolic syndromes that weirdly are all linked to each other. Diets affect the diversity of the microbiome, the diversity of the microbiome already there though, may need other macro/micro splits in order to show differing weight loss, in the case of the NND and ADD study reviewed above. Changes in weight do change the diversity of the microbiome of an individual, however, the heritable component of the microbiome may mean that some people need to eat different foods compared to others who have a different microbiome. Over time, new studies will show how and why the macro/micronutrient content matters for weight loss/gain.
Clearly, reducing the complex physiological process of weight gain/loss to numbers and ignoring the physiological process and how the microbiome induces weight gain/loss and works together with our other body’s cells. As the science grows here we will have a much greater understanding of our body’s weight loss mechanisms. Once we do that, then we can better help people with this disease.
In part II, we will look at the mental gymnastics of someone who is clueless to the data and uses whatever mental gymnastics possible in order to deny the data. Well, shit doesn’t work like that, JayMan. I will review yet more studies on sitting, walking and dieting on mortality as well as behavioral therapy (BT) in regards to obesity. JayMan has removed two of my comments so I assume the discussion is over. Good thing I have a blog so I can respond here; censorship is never cool. JayMan pushes very dangerous things and they need to be nipped in the bud before someone takes this ‘advice’ who could really benefit from lifestyle alterations. Stop giving nutrition advice without credentials! It’s that simple.
JayMan published a new article on ‘The Five Laws of Behavioral Genetics‘ with this little blip:
Indeed, we see this with health and lifestyle: people who exercise more have fewer/later health problems and live longer, so naturally conventional wisdom interprets this to mean that exercise leads to health and longer life, when in reality healthy people are driven to exercise and have better health due to their genes.
So, in JayMan’s world diet and exercise have no substantial impact on health, quality of life and longevity? Too bad the data says otherwise. Take this example:
Take two twins. Lock both of them in a metabolic chamber. Monitor them over their lives and they do not leave the chamber. They are fed different diets (one has a high-carb diet full of processed foods, the other a healthy diet for whatever activity he does); one exercises vigorously/strength trains (not on the same day though!) while the other does nothing and the twin who exercises and eats well doesn’t sit as often as the twin who eats a garbage diet and doesn’t exercise. What will happen?
Jayman then shows me Bouchard et al, (1990) in which a dozen pairs of twins were overfed for three months with each set of twins showing different gains in weight despite being fed the same amount of kcal. He also links to Bouchard et al, 1996 (can’t find the paper; the link on his site is dead) which shows that the twins returned to their pre-experiment weight almost effortlessly. This, of course, I do not deny.
This actually replicates a study done on prisoners in a Vermont prison (Salans, Horton, and Sims, 1971). “The astonishing overeating paradox” is something that’s well worth a look in to. Salans et al had prisoners overeat and also limited their physical activity. They started eating 4000 kcal per day and by the end of the study they were eating about 10000 kcal per day. But something weird happened: their metabolisms revved up by 50 percent in an attempt to get rid of the excess weight. After the study, the prisoners effortlessly returned to their pre-experiment weight—just like the twins in Bouchard et al’s studies.
The finding is nothing new but it’s nice to have replication (on top of the replication that it already had), but that’s not what I was talking about. Of course, being sedentary, eating like shit and not exercising will lead to deleterious health outcomes. The fact of the matter is, the twin in my thought experiment that did not exercise, sat around all day and ate whatever would die way sooner, have a lower quality of life, and more deleterious disease due to the shitty diet while his co-twin would have less since he ate right, exercised and spent less time sitting.
JayMan says, in regards to studies that show that obese people that even do light physical activity show lower all-cause mortality, that “That’s not what large RCTs show.” I know the study that he’s speaking of—the Look AHEAD study (Action for Health and Diabetes) (The Look AHEAD Research Group, 2009). The research group studied the effects of lifestyle interventions in type II diabetics. For one of the groups they gave intensive diet and exercise information, the other they gave only the standard advice. However, the study ended early at 9.3 years because there was no difference between both groups (Pi-Sunyer, 2015). JayMan uses this study as evidence that diet and exercise have no effect on the mortality of type II diabetics; however, in actuality, the results are much more nuanced.
Annuzzi et al (2014) write in their article The results of Look AHEAD do not row against the implementation of lifestyle changes in patients with type 2 diabetes:
The intervention aimed at weight loss by reducing fat calories, and using meal replacements and, eventually, orlistat, likely underemphasizing dietary composition. There is suggestive evidence, in fact, that qualitative changes in dietary composition aiming at higher consumption of foods rich in fiber and with a high vegetable/animal fat ratio favorably influence CV risk in T2D patients.
In conclusion, the Look AHEAD showed substantial health benefits of lifestyle modifications. Prevention of CV events may need higher attention to dietary composition, contributing to stricter control of CV risk factors. As a better health-related quality of life in people with diabetes is an important driver of our clinical decisions, efforts on early implementation of behavioral changes through a multifactorial approach are strongly justified.
They reduced far calories and used meal replacements. This is the trial JayMan is hedging his assertion on. Type II diabetics need a higher fat diet and don’t need the carbs as it will spike their insulin. Eating a higher fat diet will also lower the rate of CVD as well. This trial wasn’t too vigorous in terms of macronutrient composition. This is one of many reasons why type II diabetics discard dieting and exercise just yet.
Even modest weight loss of 5 to 10 percent is associated with significant improvements in cardiovascular disease (CVD) after one year, with larger weight loss showing better improvement (Wing et al, 2011). (Also read the article The Spinning of Look AHEAD.)
Telling diabetics not to eat right and exercise is, clearly, a recipe for disaster. This canard that dieting/exercise doesn’t work to decrease all-cause mortality—especially for diabetics and others who need the lifestyle interventions—is dangerous and a recipe for disaster.
Intentional weight loss needs to be separated from intentional weight loss as to better study the effects of both variables. Kritchevsky et al (2015) meta-analyzed 15 RCTs that “reported mortality data either as an endpoint or as an adverse event, including study designs where participants were randomized to weight loss or non-weight loss, or weight loss plus a co-intervention (e.g. weight loss plus exercise) or the weight stable co-intervention (i.e. exercise alone).” They conclude that the risk for all-cause mortality in obese people who intentionally lose weight is 15 percent lower than people not assigned to lose weight.
This study replicates a meta-analysis by Harrington, Gibson, and Cottrell (2009) on the benefits of weight loss and all-cause mortality. They noted that in unhealthy adults, weight loss accounted for a 13 percent decrease in all-cause mortality increase while in the obese this accounted for a 16 percent decrease. Of course, since the weights were self-reported and there are problems with self-reports of weight (Mann et al, 2007), then that is something that a skeptic can rightfully bring up. However, it would not be a problem since this would imply that they weighed the same/gained more weight yet had a decrease in all-cause mortality.
Even light physical activity is associated with a decrease in all-cause mortality. People who go from light activity, 2.5 hours a week of moderate physical intensity compared to no activity, show a 19 percent decrease in all-cause mortality while people who did 7 hours a week of moderate activity showed a 24 percent decrease in all-cause mortality (Woodcock et al, 2011). Even something as simple as walking is associated with lower incidence of all-cause mortality, with the largest effect being seen in individuals who went from no activity to light walking. Walking is inversely associated with disease incidence (Harner and Chida, 2008) but their analysis indicated publication bias so further study is needed. Nevertheless, the results line up with what is already known—that low-to-moderate exercise is associated with lower all-cause mortality (as seen in Woodcock et al, 2011).
What is needed to change habits/behavior is behavioral therapy (BT) (Jacob and Isaac, 2012; Buttren, Webb, and Waddren, 2012; Wilfley, Kolko, and Kaas, 2012; ). BT can also be used to increase adherence to exercise (Grave et al, 2011). BT has been shown to have great outcomes in the behaviors of obese people, and even if no weight loss/5-10 percent weight loss is seen (from Wing and Hill, 2001), better habits can be developed, and along with ‘training’ hunger hormones with lifestyle changes such as fasting, people can achieve better health and longevity—despite what naysayers may say. Though I am aware that outside of clinics/facilities, BT does not have a good track record (Foster, Makris, and Bailer, 2005). However, BT is the most studied and effective intervention in managing obesity at present (Levy et al, 2007). This is why people need to join gyms and exercise around people—they will get encouragement and can talk to others about their difficulties. Though, people like JayMan who have no personal experience doing this would not understand this.
In regards to dieting, the effect of macronutrient composition on blood markers is well known. Type II diabetics need to eat a certain diet to manage their insulin/blood sugar, and doing the opposite of those recommendations will lead to disaster.
Low-carb ketogenic diets are best for type II diabetics. There are benefits to having ketones circulating in the blood, which include (but are not limited to): weight loss, improved HbA1c levels, reduced rate of kidney disease/damage, cardiac benefits, reversing non-alcoholic fatty liver, elevated insulin, and abnormal levels of cholesterol in the blood (Westman et al, 2008; Azar, Beydoun, and Albadri, 2016; Noakes and Windt, 2016; Saslow et al, 2017). These benefits, of course, carry over to the general non-diabetic population as well.
Of course, JayMan has reservations about these studies wanting to see follow-ups—but the fact of the matter is this: dieting and eating right is associated with good blood markers, exactly what type II diabetics want. In regards to food cravings, read this relevant article by Dr. Jason Fung: Food Cravings. Contrary to JayMan’s beliefs, it’s 100 percent possible to manage food cravings and hunger. The hormone ghrelin mediates hunger. There are variations in ghrelin every day (Natalucci et al, 2005) and so if you’re feeling hungry if you wait a bit it will pass. This study lines up with most people’s personal experience in regards to hunger. One would have to have an understanding of how the brain regulates appetite to know this, though.
JayMan also cannot answer simple yes or no questions such as: Are you saying that people should not watch what they eat and should not make an effort to eat higher-quality foods? I don’t know why he is so anti-physical activity. As if it’s so bad to get up, stop sitting so much and do some exercise! People with more muscle mass and higher strength levels live longer (Ruiz et al, 2008). This anti-physical activity crusade makes absolutely no sense at all given the data. If I were to stop eating well and strength training, along with becoming a couch potato, would my chance of dying early from a slew of maladies decrease? Anyone who uses basic logic would be able to infer that the answer is yes.
I also need to address JayMan’s last comment to me which he censored:
No intervention shows that lifestyle changes extend life – or even improve health. Even if they did, their generalizability would depend on their actual prescription. In any case, the point is moot, since they don’t even show such improvements in the first place.
You’re only saying that because you’re literally hand waving away data. It’s clear that going from no exercise to some exercise will decrease all-cause mortality. I’m sorry that you have a problem reading and understanding things that you don’t agree with, but this is reality. You don’t get to construct your own reality using cherry-picked studies that don’t mean what you think they mean (like Look AHEAD; Dr. Sharma states that we may never know if weight reduction can save lives in type II diabetics, however the three studies on low-carb diets cited above lend credence to the idea that we can).
Please see my previously linked Obesity Facts page for more. Once you’ve read that, get back to me. Until then, I’m putting the brakes on this discussion.
Of course, you’re putting the brakes on this discussion, you have substantial replies other than your one-liners. You need to censor people when you have no substantial response, that’s not intellectually honest.
All in all, JayMan is giving very dangerous ‘advice’, when the literature says otherwise in regards to lifestyle interventions and all-cause mortality. You can talk about genes for this or that all you want; you’re just appealing to genes. Light physical exercise shows that mortality risk can be decreased; that’s not too hard for most people.
I know JayMan talks about genes for this and that, yet he does not understand that obesogenic environments drive this epidemic (Lake and Townshend, 2006; Powell, Spears, and Rebori, 2011; Fisberg et al, 2016). He doesn’t seem to know about the food reward hypothesis of obesity either. Think about obesogenic environments and food reward and how our brains change when we eat sugar and then things will begin to become clearer.
JayMan is giving out deadly ‘advice’, again, without the correct credentials. Clearly, as seen in both of my responses to him, taking that ‘advice’ will lead to lower quality of life and lower life expectancy. But I’m sure my readers are smart enough to not listen to such ‘advice’.
(Note: Diet and exercise under Doctor’s supervision only)
A commenter by the name of bbloggz alerted me to a new paper by Lee Ellis published this year titled Race/ethnicity and criminal behavior: Neurohormonal influences in which Ellis (2017) proposed his theory of ENA (evolutionary neuroandrogenic theory) and applied it to racial/ethnic differences in crime. On the face, his theory is solid and it has great explanatory power for the differences in crime rates between men and women, however, there are numerous holes in the application of the theory in regards to racial/ethnic differences in crime.
In part I, he talks about racial differences in crime. No one denies that, so on to part II.
In part II he talks about environmental causes for the racial discrepancies, that include economic racial disparities, racism and societal discrimination and subordination, a subculture of violence (I’ve been entertaining the honor culture hypothesis for a few months; Mazur (2016) drives a hard argument showing that similarly aged blacks with some college had lower levels of testosterone than blacks with less than high school education which fits the hypothesis of honor culture. Though Ellis’ ENA theory may account for this, I will address this below). However, if the environment that increases testosterone is ameliorated (i.e., honor culture environments), then there should be a subsequent decrease in testosterone and crime, although I do believe that testosterone has an extremely weak association with crime, nowhere near high enough to account for racial differences in crime, the culture of honor could explain a good amount of the crime gap between blacks and whites.
Ellis also speaks about the general stress/strain explanation, stating that blacks have higher rates of self-esteem and Asians the lowest, with that mirroring their crime rates. This could be seen as yet another case for the culture of honor in that blacks with a high self-esteem would feel the need to protect their ‘name’ or whatever the case may be and feel the need for physical altercation based on their culture.
In part III, Ellis then describes his ENA theory, which I don’t disagree with on its face as it’s a great theory with good explanatory power but there are some pretty large holes that he rightly addresses. He states that, as I have argued in the past, females selected men for higher rates of testosterone and that high rates of testosterone masculinize the brain, changing it from its ‘default feminine state’ and that the more androgens the brain is exposed to, the more likely it is for that individual to commit crime.
Ellis cites a study by Goodpaster et al (2006) in which he measured the races on the isokinetic dynamometry, pretty much a leg extension. However, one huge confound is that participants who did not return for follow-up were more likely to be black, obese and had more chronic disease (something that I have noted before in an article on racial grip strength). I really hate these study designs, but alas, it’s the best we have to go off of and there are a lot of holes in them that must be addressed. Though I applaud the researchers’ use of the DXA scan (regular readers may recall my criticisms on using calipers to assess body fat in the bench press study, which was highly flawed itself; Boyce et al, 2014) to assess body fat as it is the gold standard in the field.
Ellis (2017: 40) writes: “as brain exposure to testosterone surges at puberty, the prenatally-programmed motivation to strive for resources, status, and mating opportunities will begin to fully activate.” This is true on the face, however as I have noted the correlation between physical aggression and testosterone although positive is low at .14 (Archer, 1991; Book et al, 2001). Testosterone, as I have extensively documented, does cause social dominance and confidence which do not lead to aggression. However, when other factors are coupled with high testosterone (as noted by Mazur, 2016), high rates of crime may occur and this may explain why blacks commit crime; a mix of low IQ, high testosterone and low educational achievement making a life of crime ‘the smart way’ to live seeing as, as Ellis points out, and that intelligent individuals find legal ways to get resources while less intelligent individuals use illegal ways.
ENA theory may explain racial differences in crime
In part IV he attempts to show how his ENA theory may explain racial differences in crime—with testosterone sitting at the top of his pyramid. However, there are numerous erroneous assumptions and he does rightly point out that more research needs to be done on most of these variables and does not draw any conclusions that are not warranted based on the data he does cite. He cites one study in which testosterone levels were measured in the amniotic fluid of the fetus. The sample was 59 percent white and due to this, the researchers lumped blacks, ‘Hispanics’ and Native Americans together which showed no significant difference in prenatal testosterone levels (Martel and Roberts, 2014).
Umbilical cord and testosterone exposure
Ellis then talks about testosterone in the umbilical cord, and if the babe is exposed to higher levels of testosterone in vitro, then this should account for racial/ethnic differences in crime. However, the study he cited (Argus-Collins et al, 2012) showed no difference in testosterone in the umbilical cord while Rohrmann et al (2009) found no difference in testosterone between blacks and whites but found higher rates of SHBG (sex hormone-binding globulin) which binds to testosterone and makes it unable to leave the blood which largely makes testosterone unable to affect organ development. Thusly, if the finding of higher levels of SHBG in black babes is true, then they would be exposed to less androgenic hormones such as testosterone which, again, goes against the ENA theory.
He also cites two more studies showing that Asian babes have higher levels of umbilical cord testosterone than whites (Chinese babes were tested) (Lagiou et al, 2011; Troisi et al, 2008). This, again, goes against his theory as he rightly noted.
Next he talks about circulating differences in testosterone between blacks and whites. He rightly notes that testosterone must be assayed in the morning within an hour after waking as that’s when levels will be highest, yet cites Ross et al (1986) where assay times were all over the place and thusly testosterone cannot be said to be higher in blacks and whites based on that study and should be discarded when talking about racial differences in testosterone due to assay time being between 10 am and 3 pm. He also cites his study on testosterone differences (Eliss and Nyborg, 1993), but, however, just as Ross et al (1986) did not have a control for WC (waist circumference) Ellis and Nyborg (1993) did not either, so just like the other study that gets cited to show that there is a racial difference in testosterone, they are pretty hugely flawed and should not be used in discussion when discussing racial differences in testosterone. Why do I not see these types of critiques for Ross et al (1986) in major papers? It troubles me…
He also seems to complain that Lopez et al (2013) controlled for physical activity (which increases testosterone) and percent body fat (which, at high levels, decreases testosterone). These variables, as I have noted, need to be controlled for. Testosterone varies and fluctuated by age; WC and BMI vary and fluctuate by age. So how does it make sense to control for one variable that has hormone levels fluctuate by age and not another? Ellis also cites studies showing that older East Asian men had higher levels of testosterone (Wu et al, 1995). Nevertheless, there is no consensus; some studies show Chinese babes have higher levels of testosterone than whites and some studies show that whites babes have higher levels of testosterone than Chinese babes. Indeed, this meta-analysis by Ethnicmuse shows that Asians have the highest levels, followed by Africans then Europeans, so this needs to be explained to save the theory that testosterone is the cause of black overrepresentation of violence (as well as what I showed that testosterone is important for vital functioning and is not the boogeyman the media makes it out to be).
Bone density and crime
Nevertheless, the next variable Ellis talks about is bone density and its relationship to crime. Some studies find that blacks are taller than whites while other show no difference. Whites are also substantially taller than Asian males. Blacks have greater bone density than the other three races, but according to Ellis, this measure has not been shown to have a relationship to crime as of yet.
Penis size, race and crime
Now on to penis size. In two articles, I have shown that there is no evidence for the assertion that blacks have larger penises than whites. However, states that penis length was associated with higher levels of testosterone in Egyptian babes. He states that self-reported penis size correlates with self-reports of violent delinquency (Ellis and Das, 2012). Ellis’ main citations for the claim that blacks have larger penises than other races comes from Nobile (1982), the Kinsey report, and Rushton and Boagert (1987) (see here for a critique of Rushton and Boagert, 1987), though he does cite a study stating that blacks had a longer penis than whites (blacks averaging 5.77 inches while whites averaged 5.53 inches). An HBDer may go “Ahah! Evidence for Rushton’s theory!”, yet they should note that the difference is not statistically significant; just because there is a small difference in one study also doesn’t mean anything for the totality of evidence on penis size and race—that there is no statistical difference!
He then cites Lynn’s (2013) paper which was based on an Internet survey and thus, self-reports are over-measured. He also cites Templer’s (2002) book Is Size Important?, which, of course, is on my list of books to read. Nevertheless, the ‘evidence’ that blacks average larger penises than whites is extremely dubious, it’s pretty conclusive that the races don’t differ in penis size. For further reading, read The Pseudoscience of Race Differences in Penis Size, and read all of Ethnicmuses’ posts on penis size here. It’s conclusive that there is no statistical difference—if that—and any studies showing a difference are horribly flawed.
2d/4d ratio and race
Then he talks about 2d/4d ratio, which supposedly signifies higher levels of androgen exposure in vitro (Manning et al, 2008) however these results have been challenged and have not been replicated (Koehler, Simmons, and Rhodes, 2004; Yan et al, 2008, Medland et al, 2010). Even then, Ellis states that in a large analysis of 250,000 respondents, Asians had the lowest 2d/4d ratio, which if the hypothesis of in vitro hormones affecting digit length is to be believed, they have higher levels of testosterone than whites (the other samples had small ns, around 100).
Prostate-specific antigens, race, and prostate cancer
He then talks about PSA (prostate-specific antigen) rates between the races. Blacks are two times more likely to get prostate cancer, which has been blamed on testosterone. However, I’ve compiled good evidence that the difference comes down to the environment, i.e., diet. Even then, there is no evidence that testosterone causes prostate cancer as seen in two large meta-analyses (Stattin et al, 2003; Michaud, Billups, and Partin, 2015). Even then, rates of PCa (prostate cancer) are on the rise in East Asia (Kimura, 2012; Chen et al, 2015; Zhu et al, 2015) which is due to the introduction of our Western diet. I will cover the increases in PCa rates in East Asia in a future article.
He then reviews the evidence of CAG repeats. There is, however, no evidence that the number of CAG repeats influences sensitivity to testosterone. However, intra-racially, lower amounts of CAG repeats are associated with higher spermatozoa counts—but blacks don’t have higher levels of spermatozoa (Mendiola et al, 2011; Redmon et al, 2013). Blacks do have shorter CAG repeats, and this is consistent with the racial crime gap of blacks > whites > Asians. However, looking at the whole of the evidence, there is no good reason to assume that this has an effect on racial crime rates.
Intelligence and education
Next he talks about racial differences in intelligence and education, which have been well-established. Blacks did have higher rates of learning disabilities than whites who had higher levels of learning disabilities then Asians in a few studies, but other studies show whites and South Asians having different rates, for instance. He then talks about brain size and criminality, stating that the head size of males convicted for violent crimes did not differ from males who committed non-violent crimes (Ikaheimo et al, 2007). I won’t bore anyone with talking about what we know already: that the races differ in average brain size. However, a link between brain size and criminality—to the best of my knowledge—has yet to been discovered. IQ is implicated in crime, so I do assume that brain size is as well (no matter if the correlation is .24 or not; Pietschnig et al, 2015).
Prenatal androgen exposure
Now to wrap things up, the races don’t differ in prenatal androgen exposure, which is critical to the ENA theory; there is a small difference in the umbilical cord favoring blacks, and apparently, that predicts a high rate of crime. However, as noted, blacks have higher levels of SHBG at birth which inhibits the production of testosterone on the organs. Differences in post-pubertal testosterone are small/nonexistent and one should not talk about them when talking about differences in crime or disease acquisition such as PCa. DHT only shows a weak positive correlation with aggression—the same as testosterone (Christiansen and Winkler, 1992; however other studies show that DHT is negatively correlated with measures of physical aggression; Christiansen and Krussmann, 1987; further, DHT is not so evil after all).
Summing it all up
Blacks are not stronger than whites, indeed evidence from the races’ differing somatype, grip strength and leverages all have to do with muscular strength. Furthermore, the study that Ellis cites as ‘proof’ that blacks are stronger than whites is on one measure; an isokinetic dynamometry machine which is pretty much a leg extension. In true tests of strength, whites blow blacks away, which is seen in all major professional competitions all around the world. Blacks do have denser bones which is due to androgen production in vitro, but as of yet, there has been no research done into bone density and criminality.
The races don’t differ on penis size—and if they do it’s by tenths of an inch which is not statisitcally significant and I won’t waste my time addressing it. It seems that most HBDers will see a racial difference of .01 and say “SEE! Rushton’s Rule!” even when it’s just that, a small non-significant difference in said variable. That’s something I’ve encountered a lot in the past and it’s, frankly, a waste of time to converse about things that are not statistically significant. I’ve also rebutted the theory on 2d/4d ration as well. Finally, Asians had a similar level of androgen levels compared to blacks, with whites having the least amount. Along with a hole in the theory for racial differences in androgen causing crime, it’s yet another hole in the theory for racial differences in androgens causing racial differences in penis size and prostate cancer.
On intelligence scores, no one denies that blacks have scored about 1 SD lower than whites for 100 years, no one denies that blacks have a lower educational attainment. In regards to learning disabilities, blacks seem to have the highest rates, followed by Native Americans, than non-Hispanic whites, East Asians and the lowest rates found in South Asians. He states only one study links brain size to criminal behavior and it showed a significant inverse relationship with crime but not other types of offenses.
This is a really good article and I like the theory, but it’s full of huge holes. Most of the variables described by Ellis have been shown to not vary at all or much between the races (re: penis size, testosterone, strength [whites are stronger] prostate cancer caused mainly by diet, 2d/4d ratio [no evidence of it showing a digit ratio difference], and bone density not being studied). Nevertheless, a few of his statements do await testing so I await future studies on the matter. He says that androgen exposure ‘differs by race and ethnicity’, yet the totality of evidence shows ‘not really’ so that cannot be the cause of higher amounts of crime. Ellis talks about a lot of correlates with testosterone, but they do not pass the smell test. Most of it has been rebutted. In fact, one of the central tenets of the ENA theory is that the races should differ in 2d/4d ratio due to exposure of differing levels of the hormone in vitro. Alas, the evidence to date has not shown this—it has in fact shown the opposite.
ENA theory is good in thought, but it really leaves a lot to be desired in regards to explaining racial differences in crime. More research needs to be looked into in regards to intelligence and education and its effect on crime. We can say that low IQ people are more likely to drop out of school and that is why education is related to crime. However, in Mazur (2016) shows that blacks matched for age had lower levels of testosterone if they had some college under their belt. This seems to point in the direction of the ENA theory, however then all of the above problems with the theory still need to be explained away—and they can’t! Furthermore, one of the nails in the coffin should be this: East Asian males are found to have higher levels of testosterone than white males, often enough, and East Asian males actually have the lowest rate of crime in the worle!
This seems to point in the direction of the ENA theory, however then all of the above problems with the theory still need to be explained away—and they can’t! Furthermore, one of the nails in the coffin should be this: East Asian males are found to have higher levels of testosterone than white males, often enough, and East Asian males actually have some of the lowest rate of crime in the world (Rushton, 1995)! So this is something that needs to be explained if it is to be shown that testosterone facilitates aggression and therefore, crime.
I’ve shown—extensively—that there is a low positive correlation between testosterone and physical aggression, why testosterone does not cause crime, and have definitively shown that, by showing how flawed the other studies are that purport to show blacks have higher testosterone levels than whites, along with citing large-scale meta-analyses, that whites and blacks either do not differ or the differences is small to explain any so-called differences in disease acquisition or crime. One final statement on the CAG repeats, they are effect by obesity, men who had shorter CAG repeats were more likely to be overweight, which would skew readings (Gustafsen, Wen, and Koppanati, 2003). So depending on the study—and in most of the studies I cite whites have a higher BMI than blacks—BMI and WC should be controlled for due to the depression of testosterone.
It’s pretty conclusive that testosterone itself does not cause crime. Most of the examples cited by Ellis have been definitively refuted, and his other claims lack evidence at the moment. Even then, his theory rests on the 2d/4d ratio and how blacks may have a lower 2d/4d ratio than whites. However, I’ve shown that there is no significant relationship between 2d/4d ratio and traits mediated by testosterone (Kohler, Simmons, and Rhodes, 2004) so that should be enough to put the theory to bed for good.
Nutritional myths run amok everywhere. One of the most persistent is that ‘a calorie is a calorie’, that is, every macronutrient will be processed the same by the body. Another assumption is that the body doesn’t ‘care’ about where the calories come from—they can come from fat, protein, or carbs and the response will be the same: bodyweight will be reduced until one reaches their goal. However, it’s not as simple as that. He also has the assumption that “diets work”, when the best meta-analysis I know of on the matter shows the opposite (Mann et al, 2007, see especially table 1). They control for studies where weight was self-reported. They conclude that dieting does not work. This is what, as Heartiste says, “iScience!” says on the matter, so he should believe everything I state in this article, which is backed by “iScience!”.
Chateau Heartiste published an article back in 2010 titled The Twinkies Diet Proves Fatty Fats Are Fat Because They Eat Too Much. He is referring to professor of human nutrition Mark Haub and his success on ‘the twinkies diet’, where 2/3rds of his caloric intake came from junk food such as Twinkies. He lost 27 pounds in a two month period while his LDL cholesterol decreased by 20 percent and his HDL cholesterol increased by 20 percent. His level of triglycerides also decreased by 37 percent, with his body fat decreasing from 33.4 to 24.9 percent. So he ate 1800 kcal per day—2/3rds of it being junk food—for two months and lost 27 pounds. Case closed, right? Eat junk food at a deficit and lose weight? A calorie is a calorie? There are a few problems with this contention which will be addressed below.
Big bottom line: Being fat itself is bad for your health. “Fat and fit” is a myth. The change that counts the most is losing the weight, which can only be done by PUSHING AWAY FROM THE TABLE.
Except fit and overweight and obese individuals have similar mortality rates than their normal weight counterparts (Barry et al, 2014). However, more recently a study was published purporting that overweight and obese individuals being healthy despite excess weight is a myth. The researchers state that in a sample of millions of Britons that overweight and obese individuals had a higher risk of heart disease than their normal-weight counterparts. Unfortunately, I cannot locate the study since it wasn’t published in a journal (and thusly not peer reviewed). I wonder if variables such as diet, smoking and other lifestyle factors were taken into account. Nevertheless, the debate on fitness and fatness continues.
Another large meta-analysis shows that grade 1 obesity (BMI 30->35) had the same mortality risk as normal-weight individuals with grade 2 obese (BMI +35) having a significantly higher risk of death (Flegal, Kit, and Orpana, 2013).
Heartiste claims that ‘a calorie is a calorie’. This is a common fallacy. This suggests that the body will process all foods the same way—that is, processing them the same metabolically. This, however, is not the case. Haub himself is a sample size of 1. If Heartiste can use a sample size of 1 to make a claim, then I can too.
Sam Feltham ate +5,000 kcal per day for 21 days and only gained 1.3 kg when he should have gained 7.3 kg based on the amount of kcal he ate. A calorie is a calorie, right? This is a fallacious statement. The statement “a calorie is a calorie” violates the second law of thermodynamics (Feinman and Fine, 2004). Heartiste writes:
That first law of thermodynamics looms large over everything.
The first law of thermodynamics is irrelevant to human physiology. It only states that an organism gets bigger if it consumes more energy; it doesn’t state why this occurs, which is due to the hormone insulin which causes weight gain.
He does rightly state that an omega 3/6 imbalance is part of the reason but then handwaves it away. Western-like high-fat diets (i.e., diets with an imbalance of linoleic acids (LA; and n-6 fatty acid) with n-3) are sufficient enough to induce gradual enhancement in fat mass across the generations (Massiera et al, 2010). This obviously includes the average 55 percent carbohydrate diet that the AHA recommends (Eckel et al, 2014). The Standard American Diet (aptly named the “SAD diet”) has the n-3/n-6 imbalance along with being high in carbohydrates which spike insulin which impedes fat being unlocked from the adipocyte.
Heartiste doesn’t understand that if you reduce the ‘in’, the ‘out’ also decreases. This was noted in the famous starvation experiment headed by Ancel Keys. They took 36 healthy men who ate normally for three months while being their behavior and personality was monitored. In the next six months, they were reduced to eating half of their initial intake (they started at 2000 kcal and dropped to 1000 kcal; some individuals going lower than that) and their metabolic rate decreased by 40 percent (Keys et al, 1945). This is proof for the contention that the body decreases its metabolic rate due to what is ingested. A similar study was done on Vermont prisoners, except they were told to gorge on food. Since they were in a controlled setting, the prisoners could be monitored to ensure they ate all of the food.
At the end of the study, their metabolic rates had increased by 50 percent. This is evidence that the body was trying to get back to its original weight. In six months, the prisoners went back to their normal weight as they ate normally (Salas, Horton, and Sims, 1971) One man only gained ten pounds eating all of those calories. Clearly, the body was resisting weight gain and when they were allowed to eat normally, they effortlessly regained their normal weights.
Finally, on the topic of Haub, Big Food shill, I will address a few things about him and his ‘research’ that recently came to light.
Intermittent fasting and obesity expert Dr. Jason Fung showed that in 2016 after Coca-Cola released their funding reports after criticisms of transparency, Mark Haub was found to be one of the many researchers that were backed by Coca-Cola. This is an attempt to show that ‘a calorie is a calorie’ and that ‘all calories are created equal’. This has been rebutted above.
In 2016—six years after his ‘experiment—it was revealed that he was funded by Coca-Cola. No doubt in order to ‘prove’ that ‘a calorie is a calorie’ and have people continue to gorge on high carbohydrate/insulinogenic foods. However, the human body is a lot more complex than to just reduce it to simply calories in and calories out—which I have written about in depth.
People like Heartiste need to get an actual understanding of the literature and what Coca-Cola has been trying to do for years, which is to make eating junk food ‘OK’ because ‘it doesn’t cause obesity’. Children consume 45 percent more food when exposed to advertisements (Harris, Bargh, and Brownell, 2009). So to begin to curb obesity rates we don’t need to ‘eat junk food’, we need to not eat junk food and eat a diet more ancestral to us—that is, one lower in processed carbs and higher in animal fat and protein. Big Food shills like Haub need to be exposed for what they are—people who do ‘research’ for a quick buck, i.e., not furthering our understanding of a complex issue as he would like you to believe. Exercise also doesn’t induce weight loss. So the claims of ‘eat less and move more’ (eat less according to the 55 percent carbohydrate recommendations) is bound to fail.
If Heartiste can make a claim using one man as an example then so can I. Read the above article by Sam Feltham in which he writes about hs experience eating 5,000 kcal per day for 21 days while only gaining 1.3 kg. I can use this example to say that eating low carb and high fat at 5,000 kcal per day will lead to negligible weight gain, however, I don’t use n=1 sample sizes to make claims and no one else should either.
By Scott Jameson
I’ve been active in the blogosphere for around 24 hours now and I’ve already gotten a negative response from someone who happens to be wrong. That’s a win in my book.
The argument we’re having is, as best I can tell, why some populations out there just don’t have obesity as an observed phenotype amongst their members. TL;DR: Pumpkin Person and Robert Lindsay believe that genetics explain why there are no obese New Guineans. But it ain’t so.
The original context is an old Pumpkin Person post. Much of what he’s saying here doesn’t seem too off-base; for example he says that behavioral genetics may explain much of the differences in BMI between individuals within the same population. True. It is possible that some people are genetically inclined to eat more or unhealthier foods, rather than simply being genetically inclined to putting on weight regardless of what they do.
As an aside, genotypes that affect how you digest things also probably explain part of the BMI gap between skinny folks and fat folks within the first world. The APOA2 gene for example has a recessive allele that is associated with higher BMI in people who eat more saturated fats. The interactions between genes and environment which determine BMI are complicated and not yet fully understood, but I’m willing to bet that being genetically worse at processing certain nutrients is a part of the problem, and that being genetically inclined to stuff your face is a part of the problem as well. PP is probably right about that issue.
Where he and Lindsay get it wrong is using examples of people from Podunk, New Guinea as evidence for obesity “being genetic” (relative term). Obesity is a gene-environment interaction such that, without certain environmental inputs, you simply won’t get the phenotype. History tells us that that input is processed carbohydrates.
There was a time when people could have used Australian Aboriginals or Inuit or Pima Indians as examples of groups of people who just don’t have obese folks amongst their numbers, just as Lindsay did with a few populations. Homo sans lardicus. Then the White Devils showed up with their refined Einkorn wheat products and their firewater and so on. Now those populations have fat people in them.
There’s an ongoing debate as to whether some populations are more resistant to the fattening effects of processed carbs or not. My guess is, the answer’s yes (and you’d look at Europeans and East Asians to see the more carb-resistant people, in theory) but that topic would merit its own post. That being said, every population in the world will almost assuredly have obese people in it after you introduce processed carbs. All of the populations that were introduced to this diet, now have fat people in them.
Heritability of BMI is high within the first world because the relevant environmental input is pretty uniform: everybody has access to potatoes, everybody has access to broccoli. As PP points out, which you’re likely to eat and how much you’re likely to eat likely depends on your genetics. As I point out, how your body processes the nutrients also has a likely genetic component. But the environmental contribution to our within-population differences in BMI is low (~20%) because we all have access to roughly the same stuff.
Rural New Guineans, lacking a bunch of processed carbs, could hardly get fat if they tried their best to. That’s a big between-population, nonheritable cause for a phenotypic difference; this means that environment probably explains most of the BMI gap between them and us. If I wanted evidence to refute Lindsay’s assertion that New Guineans are skinnier thanks to genetics, I’d find a population of urbanized New Guineans somewhere with higher average BMI. Such a group would have New Guinean genetics but a “developed” environment vaguely similar to ours; if they were fatter than their rural ken, then Lindsay’s hypothesis that New Guineans are just genetically obesity-free would be falsified.
I come across a lot of ridiculous articles from PumpkinPerson, but this has to be one of the most ridiculous. He writes:
Identical twin studies show that obesity has a heritability of almost 80%. Although I generally lean towards nature in most nature-nurture debates, I’ve always had a problem with the idea that obesity is highly genetic, and thus enjoyed this epic rant by blogger Robert Lindsay:
It is 80% genetic[?]
That is why you have whole tribes in South America where not one person has ever been fat.
That is why you have whole towns in Melanesia with 1000’s of people where not one person is fat.
There are fat people in the cities of Solomon Islands. In the study I read, the only man who was fat was one who had gone off to the city for a while and ate salt and processed, packaged food. Do you realize that if you did a genetic study of the fatties in Melanesia, you would find that wonderful 80% “genetic” link you guys are shouting about?
That is why the fatness and obesity rate has exploded in the US and much of the rest of the world. Because it’s 80% genetic!
I do not believe that fatsos act just like the rest of us. Ever known a blimp who ate like a bird? Me either.
I dunno about you, but I have never seen a fat person who wasn’t stuffing their face all the time with lousy food. They are always in restaurants. Always going out to eat. If you go to a restaurant, look around at all the fat people. Those people are fat because fat people like to eat out all the time and restaurant food is fattening. Fat people love to eat. Have you ever noticed that?
It’s 80 percent heritable in first world countries. Obviously the heritability will be lower in the third world. Clearly in first-world countries we have an overabundance of food. We don’t know what to do with it. So instead of having the opposite problem (not enough food) we now have too much food and this is what caused weight to increase (along with added sugars processed carbs).
Look at Melanesia—they still eat an ancestral diet. I can’t tell if Lindsay is being serious or not. He’s comparing people who still eat their ancestral diet to people who live in first-world countries and eat a Western diet. There’s no comparison there. If you want to see why people aren’t fat nor have the same diseases at the same rates (they are low to nonexistent in places like that) read Agriculture and Diseases of Civilization.
This is the study that’s being referred to Elks et al 2012. The heritability of BMI is between .75 and .82. Again: this is in first-world countries.
PP then says:
In fact just the other day, I was at the home of someone who was so incredibly fat I thought “it must be genetic.” And then just as I was leaving his house, I noticed a huge empty box of pizza in the kitchen.
“So maybe the answers to be found are in the integration of factors – starting with the physiological, metabolic, and genetic ones and letting them lead us to the environmental triggers. Because the one thing we know for sure is that the laws of thermodynamics, true as they always are, tell us nothing about why we get fat or why we take in more calories than we expend while it’s happening. (emphasis mine) (Taubes, 2011: pg 74, excerpt from Why We Get Fat and What to Do About It)
The fatness itself or the tendency to engage in behaviors that cause fatness such as ordering large pizzas? So while obesity might technically be nearly 80% genetic, the statistic is misleading because it’s not directly genetic in the same was as height is.
If you don’t eat enough, nor get the right nutrients, you don’t hit your genetic height. If you don’t eat enough you don’t hit your genetic weight.
I don’t get why studies like this get generalized to the whole population. This study was done in first-world countries and so this only applies to first-world countries. You’d think that people who think they know science would know that studies are only applicable for the cohort and people they are done on. Guess not.
Of course I don’t deny obesity has some direct genetic component. Some people gain weight a lot easier than others and for some people, it’s virtually impossible to lose weight no matter how well they eat, though this is rare.
Of course some people gain weight easier than others. Some people lose weight easier than others. Much of the biological opposition to sustained weight loss is due to the hormone leptin (Rosenbaum et al, 2010). The more fat you have in your body, the more leptin you have. Moreover, the longer you are at a certain weight, the more likely it is that is your bodyweight set-point and thus you can only move up or down at around a range of 10 to 15 pounds. Also see this quote from neuroscientist Sandra Aamodt’s book Why Diets Make Us Fat (see her Ted Talk here):
Like nearsightedness, environmental influences on weight also mostly affect the genetically vulnerable, although we understand the details of the process in only rare cases. Fitness gains on a standardized exercise program vary from one person to another largely because of differences in their genes. When identical twins, men in their early twenties, were fed an extra thousand calories per day for about three months, each pair showed similar weight gains . In contrast, the gain varied across twin pairs, ranging from nine to twenty-nine pounds, even though the caloric imbalance was the same for everyone. An individual’s genes also influence weight loss. When another group of identical twins burned a thousand more calories per day through exercise while maintaining a stable food intake in an in-patient facility, their losses ranged from two to eighteen pounds and were even more similar within twin pairs than weight gain. (Aamodt, 2016 pg. 138)
The cold, hard truth is that dieting doesn’t have a good track record. See Mann et al (2007) here. People don’t understand the bodies’ biological processes and assume something is easy while being ignorant to how the body reacts under caloric deprivation. This wouldn’t happen if people actually had some knowledge of human physiology. Something that PP and RL lack. They are speaking about a complex problem than they’re too ignorant to really know about.
PP then says:
“Now I have no doubt that if that person has an identical twin raised apart, he too is extremely fat, and thus fatness technically has a high heritability, but what exactly is genetic here?”
Would the identical twin be raised in an obesogenic environment? If so, there’s a high chance that, yes he’d be fat too.
It’s also true that most people who lose weight end up gaining it back, but that’s because they end up returning to their compulsive eating habits.
People should read a few papers and books to see some data and facts before they write what “sounds good” in their head. These two clearly have no idea what they’re talking about and clearly talking from emotion and what sounds good.
Also read Are There Genetic Causes for Obesity?
Diet is the main driver of our evolution. Without adequate energy, we wouldn’t be able to able to have a brain as large as we do that has the number of neurons we have due to how calorically expensive each neuron is (6 kcal per billion neurons). However, as I’m sure everyone can see, our current diets and environment has caused the current obesity crisis in the world. What is the cause of this? Our genomes are adapted for a paleolithic diet and not our modern environment with processed foodstuffs along with an overabundance of energy. With an overabundance of novel food items and situations due to our obesogenic environments, it is easier for a higher IQ person to stay thinner than it is for a lower IQ person. Tonight I will talk about the causes for this, how and what we evolved to eat and, of course, how to reverse this phenomenon.
“Gourmet Sapiens” arose around 1-1.5 mya with the advent of cooking by Homo erectus. Even before then, when we became bipedal our hands were freed which then allowed us to make tools. With these tools, we could mash and cut food which was a sort of pre-digestion outside the body (exactly what cooking is). Over time, our guts shrank (Aiello, 1997) and we became adapted for a certain diet (Eaton, 2006). Over time, we evolved to eat a certain way—that is, we had times of feast and famine. Due to this, eating three meals a day is abnormal from an evolutionary perspective (Mattson et al, 2014). This sets the stage for the acquisition of diseases of civilization along with the explosion of obesity rates.
When looking for the causes—and not symptoms—of the rise of obesity rates, the first thing we should do is look at our current environment. How is it constructed? What type of foodstuffs are in it? What kinds of foods get advertised to us and how does this have an effect on our psyche and what we eventually buy? All three of these questions are extremely important to think of when talking about why we are so obese as a society. First-world environments are obesogenic (Galgani and Ravussin, 2008) due to being evolutionarily novel. Our genomes are adapted to a paleolithic diet, and so the introduction of the neolithic diet and agriculture reduced our quality of life, with a marked decrease in the quality of skeletal remains discovered after the advent of agriculture. However, agriculture is obviously responsible for the population boom that allowed us to become the apes the took over the world, cause being the population boom that followed the agricultural revolution (Richards, 2002).
Evolutionary mismatches occur when the rate of cultural or technological change is far faster than the genome can change to adapt to the new pressure. These dietary mismatches occur when cultural and technological change which can vastly outstrip biological evolution. The two big events that occurred in human history that have vastly outstripped biological evolution are the agricultural and Industrial Revolution. Contrary to Ryan Faulk’s belief, East Asians are not ‘less sensitive to carbohydrates’ and he did not “solve Gary Taubes’ race problem” in regards to diabesity rates. The rate of cultural and technological change has had large deleterious effects on our quality of life, and our increasing obesity rates have a lot to do with it.
Cofnas (2016) showed that mice taken off of their ancestral diet lead to worse healthy outcomes. The results of Lamont et al (2016) show that we, as animals, are adapted for ancestral diets, not the diets of the environment we have currently made for ourselves. This is a big point to take home from this. All organisms are adapted/evolved for what occurred in the ancestral past, not any possible future events. Therefore, to be as healthy as possible, it stands to reason you should eat a diet that’s closer to the ones your ancestors ate, especially since it can reverse type II diabetes and reverse bad blood markers (Klonoff, 2009). Even a short-term switch to a paleo diet “improves BP and glucose tolerance, decreases insulin secretion, increases insulin sensitivity and improves lipid profiles without weight loss in healthy sedentary humans.” (Frassetto et al, 2009) Since we evolved for a past environment and not any possible future ones, then eating a diet that’s as close as possible to our paleolithic ancestors looks like a smart way to beat the evolutionary mismatch in terms of our new, current obesogenic environment.
In one extremely interesting study, O’dea (1984) took ten middle-aged Australian Aborigines with type 2 diabetes and had them return to their ancestral hunter-gatherer lifestyle. With seven weeks of an ancestral diet and exercise, the diabetes had almost completely reversed! Clearly, when the Aborigines were taken off of our Western diet and put back in their ancestral environment with their ancestral diet, their diabetes disappeared. If we went back to a more ancestral eating pattern, the same would happen with us. This one small study lends credence to my claim that we need to eat a diet that’s more ancestral to us for us to ameliorate diseases of civilization (Eaton, 2006).
Further, looking at obesity from an evolutionary perspective can and will help us understand the disease of obesity (Ofei, 2005) better. Speakman (2009) reviewed three different explanations of the current obesity epidemic and assessed their usefulness in explaining the epidemic. The thrifty gene hypothesis states that obesity is an adaptive trait, that people who carry so-called ‘thrifty genes’ would be at an adaptive advantage. And since we have an explosion of obesity today from the 70s to today, this must explain a large part of the variance, right? There is evidence pointing in this direction, however (Southam et al, 2009). The second cause that Speakman looks at is the adaptive viewpoint—that obesity may have never been advantageous in our history, but genes that ultimately predispose us to obesity become “selected as a by-product of selection on some other trait that is advantageous.” (Speakman, 2009) The third and final perspective he proposes is that it’s due to random genetic drift, called ‘drifty genes’, predisposing some—and not others—to obesity. Whatever the case may be, there is some truth to their being genetic factors involved in the acquisition of fat storage. Though drifty genes and the adaptive viewpoint on obesity make more sense than any thrifty gene hypothesis.
For there to be any changes in the rate of obesity in the world, we need to begin to change our obesogenic environments to environments that are more like our ancestral one in terms of what foods are available. Once we alter our obesogenic environment into one that is more ancestrally ‘normal’ (since we are adapted for our past environments and not any possible future ones) then and only then will we see a reduction in obesity around the world. We are surrounded and bombarded with ads since we are children, which then effects our choices later in life; children consume 45 percent more when exposed to advertising (Harris et al, 2009). Clearly, advertisements can have one eat more, and the whole environmental mismatch in regards to being surrounded by foodstuffs not ancestral to us causes the rate of obesity to rise.
Finally, one thing we need to look at is the n-3 to n-6 ratio of our diets. As I covered last month, the n-6/n-3 is directly related to cognitive ability (Lassek and Gaulin, 2011). Our obesogenic environments cause our n-3/n-6 levels to be thrown out of whack. Our hunter-gatherer ancestors had a 1:1 level of n-3 and n-6 (Kris-Etherton, 2000). However, today, our diets contain 14 to 25 times more n-6 than n-3!! Still wondering why we are getting stupider and fatter? Further, Western-like diets (high in linolic acid; an n-6 fatty acid) induces a general fat mass enhancement, which is in line with the observation of increasing obesity in humans (Massiera et al, 2010). There is extreme relevance to the n-3/n-6 ratio on human health (Griffin, 2008), so to curb obesity and illness rates, we need to construct environments that promote a healthy n-3/n-6 ratio, as that will at least curb the intergenerational transmission of obesity. Lands (2015) has good advice: “A useful concept for preventive nutrition is to NIX the 6 while you EAT the 3.” Here is a good list to help balance n-6 to n-3 levels.
In sum, obesity rates are a direct product of obesogenic environments. These environments cause obesity since we are surrounded by evolutionary novel situations and food. The two events in human history that contribute to this is the agricultural and Industrial Revolution. We have paleolithic genomes in a modern-day world, which causes a mismatch between our genomes and environment. This mismatch can be ameliorated if we construct differing environments—ones that are less obesogenic with less advertisement of garbage food—and we should see rates of obesity begin to decline as our environment becomes more and more similar to our ancestral one (Genné-Bacon, 2014).
The study on mice showed that for them to be healthy they need to eat a diet that is ancestral to them. We humans are no different.The evidence from the study on Australian Aborigines and the positive things that occur after going on a paleo diet for humans—even for sedentary people—shows that for us to be as healthy as possible in these obesogenic environments that we’ve made for ourselves, we need to eat a diet that matches with our paleolithic genome. This is how we can begin to fight these diseases of civilization and heighten our quality of life.
Note: Diet and exercise only under Doctor’s supervision, of course
Aiello, L. C. (1997). Brains and guts in human evolution: The Expensive Tissue Hypothesis. Brazilian Journal of Genetics,20(1). doi:10.1590/s0100-84551997000100023
Cofnas, N. (2016). Methodological problems with the test of the Paleo diet by Lamont et al. (2016). Nutrition & Diabetes,6(6). doi:10.1038/nutd.2016.22
Eaton, S. B. (2006). The ancestral human diet: what was it and should it be a paradigm for contemporary nutrition? Proceedings of the Nutrition Society,65(01), 1-6. doi:10.1079/pns2005471
Frassetto, L. A., Schloetter, M., Mietus-Synder, M., Morris, R. C., & Sebastian, A. (2009). Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet. European Journal of Clinical Nutrition,63(8), 947-955. doi:10.1038/ejcn.2009.4
Galgani, J., & Ravussin, E. (2008). Energy metabolism, fuel selection and body weight regulation. International Journal of Obesity,32. doi:10.1038/ijo.2008.246
Genné-Bacon EA, Thinking evolutionarily about obesity. Yale J Biol Med 87: 99–112, 2014
Griffin, B. A. (2008). How relevant is the ratio of dietary n-6 to n-3 polyunsaturated fatty acids to cardiovascular disease risk? Evidence from the OPTILIP study. Current Opinion in Lipidology,19(1), 57-62. doi:10.1097/mol.0b013e3282f2e2a8
Harris, J. L., Bargh, J. A., & Brownell, K. D. (2009). Priming effects of television food advertising on eating behavior. Health Psychology,28(4), 404-413. doi:10.1037/a0014399
Klonoff, D. C. (2009). The Beneficial Effects of a Paleolithic Diet on Type 2 Diabetes and other Risk Factors for Cardiovascular Disease. Journal of Diabetes Science and Technology,3(6), 1229-1232. doi:10.1177/193229680900300601
Kris-Etherton PM, Taylor DS, Yu-Poth S, et al. Polyunsaturated fatty acids in the food chain in the United States. Am J Clin Nutr, 2000, vol. 71 suppl(pg. 179S-88S)
Lamont, B. J., Waters, M. F., & Andrikopoulos, S. (2016). A low-carbohydrate high-fat diet increases weight gain and does not improve glucose tolerance, insulin secretion or β-cell mass in NZO mice. Nutrition & Diabetes,6(2). doi:10.1038/nutd.2016.
Lands, B. (2015). Choosing foods to balance competing n-3 and n-6 HUFA and their actions. Ocl,23(1). doi:10.1051/ocl/2015017
Lassek, W. D., & Gaulin, S. J. (2011). Sex Differences in the Relationship of Dietary Fatty Acids to Cognitive Measures in American Children. Frontiers in Evolutionary Neuroscience,3. doi:10.3389/fnevo.2011.00005
Massiera, F., Barbry, P., Guesnet, P., Joly, A., Luquet, S., Moreilhon-Brest, C., . . . Ailhaud, G. (2010). A Western-like fat diet is sufficient to induce a gradual enhancement in fat mass over generations. The Journal of Lipid Research,51(8), 2352-2361. doi:10.1194/jlr.m006866
Mattson, M. P., Allison, D. B., Fontana, L., Harvie, M., Longo, V. D., Malaisse, W. J., . . . Panda, S. (2014). Meal frequency and timing in health and disease. Proceedings of the National Academy of Sciences,111(47), 16647-16653. doi:10.1073/pnas.1413965111
O’dea, K. (1984). Marked improvement in carbohydrate and lipid metabolism in diabetic Australian aborigines after temporary reversion to traditional lifestyle. Diabetes,33(6), 596-603. doi:10.2337/diabetes.33.6.596
Ofei F. Obesity- a preventable disease. Ghana Med J 2005;39: 98-101
Richards, M. P. (2002). A brief review of the archaeological evidence for Palaeolithic and Neolithic subsistence. European Journal of Clinical Nutrition,56(12), 1270-1278. doi:10.1038/sj.ejcn.1601646
Southam, L., Soranzo, N., Montgomery, S. B., Frayling, T. M., Mccarthy, M. I., Barroso, I., & Zeggini, E. (2009). Is the thrifty genotype hypothesis supported by evidence based on confirmed type 2 diabetes- and obesity-susceptibility variants? Diabetologia,52(9), 1846-1851. doi:10.1007/s00125-009-1419-3
Speakman, J. R. (2013). Evolutionary Perspectives on the Obesity Epidemic: Adaptive, Maladaptive, and Neutral Viewpoints. Annual Review of Nutrition,33(1), 289-317. doi:10.1146/annurev-nutr-071811-150711
The relationship between exercise and cognitive ability is important, but often not spoken about. Exercise releases many endorphins (Harber and Sutton, 1984) that help to further positive mood, have one better handle stress since sensitivity to stress is reduced after exercise; and after exercise, depression, and anxiety also decrease (Salmon, 2001). Clearly, if you’re attempting to maximize your cognition, you want to exercise. However, a majority of Americans don’t exercise (49 percent of Americans over the age of 18 do aerobic exercise whereas only 20 percent of Americans do both aerobic and muscle-strengthening exercise). The fact that we do not exercise as a country is proof enough that our life expectancy is declining (Olshansky et al, 2005), and we need to exercise—as a country—to reverse the trend.
Regular readers may know of my coverage of obesity on this blog. Understandably, a super majority of people will disregard my views on obesity and its causes as ‘pseudoscience’ or ‘SJW-ness’, that however says nothing to the data (and if anyone would like to discuss this, they can comment on the relevant articles). Since the average American hardly gets any exercise, this can lead to a decrease in cognitive functioning as less blood flows to the brain. Thus, everyone—especially the obese—needs to exercise to reach maximum genetic brain performance, lest they degenerate in cognitive function due a low-quality diet, such as a diet high in n-6 (the SAD diet), which is correlated with decreased cognition. Further, contrary to popular belief, the obese have lower IQs since around age three; obesity does not itself lower genotypic IQ, their IQ is ALREADY LOW which leads to obesity later in life due to a non-ability to delay gratification. Clearly, exercise education needs to be targeted at those with lower IQs since they have a higher chance of becoming obese in comparison to those with lower IQs (Kanazawa, 2013; 2014).
Clearly not eating well and not exercising can have negative effects on cognition. But what are the positives?
As mentioned previously, exercise releases endorphins that cause good mood and block pain. However, the importance of exercise does not stop there. Exercise also leads to faster reaction times on memory tasks and “increased levels of high-arousal positive affect (HAP) and decreased levels of low-arousal positive affect (LAP).” Exercise has important effects on people of all age groups (Hogan, Mata and Carstensen, 2013; Chodzko-Zajko et al, 2009). Further, physical exercise protects against age-related diseases and cognitive decline in the elderly by modifying “metabolic, structural, and functional dimensions of the brain that preserve cognitive performance in older adults.” (Kirk-Sanchez and McGough, 2014). Exercise is, clearly, a brain protectant during both adolsence and old age, so no matter your age if you want a high QoL living the best life possible, you need to supplement an already healthy lifestyle with strength training/cardio (of course, under doctor’s supervision).
Another important benefit to exercise is that it increases blood flow to the brain (Querido and Steele, 2007; Willie and Ainslie, 2011); however, changes in cerebral blood flow (CBF) during exercise are not associated with higher cognition (Ogoh et al, 2014). During prolonged exercise, cognition was improved when blood flow to the middle cerebral artery (MCA) was decreased. Thusly, exercise-induced changes in CBF do not preserve cognitive performance. Exercise to get blood to the brain is imperative for proper brain functioning. Our brains are vampiric, so we need to ‘feed it’ with blood and what’s the best way to ‘feed’ the brain in this context? Exercise!
Exercise also protects against cognitive degeneration in the elderly (Bherer, Erikson and Lie-Ambrose, 2013; Carvalho et al, 2014; Paillard, 2015). Further, longitudinal studies show an association between exercise and a decrease in dementia (Blondell, Hammersley-Mather and Veerman, 2014). The evidence is currently piling up showing that exercise at all ages is good cognitively, reduces mortality as well as a whole slew of other age-related cognitive diseases. The positive benefits of exercise need to be shown to elderly populations since exercise—mainly strength training—reduces the chance of osteoporosis (Layne and Nelson, 1999; Gray, Brezzo, and Fort, 2013). Moreover, elderly people who exercise live longer (Gremeaux et al, 2012). Now, if you don’t exercise, now’s looking like a pretty good time to start, right?
Finally, lack of exercise causes a myriad of deleterious diseases (Booth, Roberts, and Laye, 2014). This is due, in large part to our evolutionary novel environment (Kanazawa, 2004) which leads to evolutionary mismatches. An evolutionary mismatch, in this instance, is our obesogenic environment (Lake and Townshend, 2006). In terms of our current environment, it is evolutionary novel in comparison to our ancestral land (the Savanna; re: Kanazawa, 2004). Modern-day society is ‘evolutionarily novel’. In this case, we haven’t fully adapted (genetically) to our new lifestyles as, Gould said in Full House, our rate of cultural change has vastly exceeded Darwinian selection. Thusly, our environments that we have made for ourselves (and that we assume that heighten our QoL) actually cause the reverse, all the while top researchers are scratching their heads to figure out the answer, the problem while it’s staring them right in the face.
Our obesogenic environments have literally created a mismatch with our current eating habits and our ancestral one (Krebs, 2009). Moreover, dietary mismatches occur when cultural and technological change vastly outstrip biological evolution (Logan and Jacka, 2009). Clearly, we need to lessen the impact of our obesogenic environment we have made for ourselves so that we can live as long as possible, as well as be as cognitively sharp as possible. Thusly, if our environment causes a mismatch with our genome which in turn causes obesity, then by changing our environment to one that matches our genome, so to speak, levels of obesity should decline as our environment becomes less obesogenic while becoming like our ancestral environment (Genne-Bacon, 2014).
In sum, the evidence for the positive benefits for exercise is ever-mounting (not like you need Pubmed studies to know that exercise is beneficial). However, due to our obesogenic environments, this makes it hard for people with higher time preference to resist their urges and the result is what you see around you today. The evidence is clear: exercise leads to increased blood flow to our vampiric brains; thus it will have positive effects on memory and other cognitive faculties. So, in order to live to a ripe, old age as a healthy man/woman, hit the gym and treadmill and try staying away from evolutionarily novel things as much as possible (i.e., like processed food). When we, as a country recognize this, we can then be smarter, healthier and, above all else, have a high QoL while living a longer life. Is that not what we all want? Well hit the gym, start exercising and change your diet to one that matches our ancestors. Don’t be that guy/gal (we all know who that guy is) that jumps on the exercise train late and misses out on these cognitive and lifestyle benefits!
Note: Only with Doctor supervision, of course
Bherer, L., Erickson, K. I., & Liu-Ambrose, T. (2013). A Review of the Effects of Physical Activity and Exercise on Cognitive and Brain Functions in Older Adults. Journal of Aging Research,2013, 1-8. doi:10.1155/2013/657508
Blondell, S. J., Hammersley-Mather, R., & Veerman, J. L. (2014). Does physical activity prevent cognitive decline and dementia?: A systematic review and meta-analysis of longitudinal studies. BMC Public Health,14(1). doi:10.1186/1471-2458-14-510
Booth, F. W., Roberts, C. K., & Laye, M. J. (2013). Lack of Exercise Is a Major Cause of Chronic Diseases. Comprehensive Physiology. doi:10.1002/cphy.c110025
Carvalho, A., Cusack, B., Rea, I. M., & Parimon, T.,. (2014). Physical activity and cognitive function in individuals over 60 years of age: a systematic review. Clinical Interventions in Aging, 661. doi:10.2147/cia.s55520
Chodzko-Zajko WJ, Proctor DN, Fiatarone Singh MA, Minson CT, Nigg CR, Salem GJ, Skinner JS: American College of Sports Medicine position stand. Exercise and physical activity for older adults. Med Sci Sports Exerc. 2009, 41: 1510-1530. 10.1249/MSS.0b013e3181a0c95c.
Gray M., Di Brezzo R., I.L. Fort (2013) The effects of power and strength training on bone mineral density in premenopausal women. J Sports Med Phys Fitness, 53, pp. 428–436
Genné-Bacon EA, Thinking evolutionarily about obesity. Yale J Biol Med 87: 99–112, 2014
Gremeaux V, Gayda M, Lepers R, Sosner P, Juneau M, Nigam A. Exercise and longevity. Maturitas. 2012;73(4):312–7.
Harber VJ, Sutton JR. (1984) Endorphins and exercise. Sports Medicine 1: 154–174, 1984
Hogan, C. L., Mata, J., & Carstensen, L. L. (2013). Exercise holds immediate benefits for affect and cognition in younger and older adults. Psychology and Aging,28(2), 587-594. doi:10.1037/a0032634
Kanazawa, S. (2004). The Savanna Principle. Managerial and Decision Economics,25(1), 41-54. doi:10.1002/mde.1130
Kanazawa, S. (2013). Childhood intelligence and adult obesity. Obesity,21(3), 434-440. doi:10.1002/oby.20018
Kanazawa, S. (2014). Intelligence and obesity. Current Opinion in Endocrinology & Diabetes and Obesity,21(5), 339-344. doi:10.1097/med.0000000000000091
Krebs, J. R. (2009). The gourmet ape: evolution and human food preferences. American Journal of Clinical Nutrition,90(3). doi:10.3945/ajcn.2009.27462b
Lake, A., & Townshend, T. (2006). Obesogenic environments: exploring the built and food environments. The Journal of the Royal Society for the Promotion of Health,126(6), 262-267. doi:10.1177/1466424006070487
Layne, J. E., & Nelson, M. E. (1999). The effects of progressive resistance training on bone density: a review. Medicine & Science in Sports & Exercise,31(1), 25-30. doi:10.1097/00005768-199901000-00006
Kirk-Sanchez, N., & Mcgough, E. (2014). Physical exercise and cognitive performance in the elderly: current perspectives. Clinical Interventions in Aging, 51. doi:10.2147/cia.s39506
Ogoh, S., Tsukamoto, H., Hirasawa, A., Hasegawa, H., Hirose, N., & Hashimoto, T. (2014). The effect of changes in cerebral blood flow on cognitive function during exercise. Physiological Reports,2(9). doi:10.14814/phy2.12163
Olshansky, S. J., Passaro, D. J., Hershow, R. C., Layden, J., Carnes, B. A., Brody, J., . . . Ludwig, D. S. (2005). A Potential Decline in Life Expectancy in the United States in the 21st Century. New England Journal of Medicine,352(11), 1138-1145. doi:10.1056/nejmsr043743
Paillard, T. (2015). Preventive effects of regular physical exercise against cognitive decline and the risk of dementia with age advancement. Sports Medicine – Open,1(1). doi:10.1186/s40798-015-0016-x
Querido, J. S., & Sheel, A. W. (2007). Regulation of Cerebral Blood Flow During Exercise. Sports Medicine,37(9), 765-782. doi:10.2165/00007256-200737090-00002
Salmon, P. (2001). Effects of physical exercise on anxiety, depression, and sensitivity to stress. Clinical Psychology Review,21(1), 33-61. doi:10.1016/s0272-7358(99)00032-x
Willie, C. K., & Ainslie, P. N. (2011). Cool head, hot brain: cerebral blood flow distribution during exercise. The Journal of Physiology,589(11), 2657-2658. doi:10.1113/jphysiol.2011.209668
It is assumed that since the advent of agriculture that we’ve been better nourished than our hunter-gatherer ancestors. This assumption stems from the past 130 years since the advent of the Industrial Revolution and the increase in the quality of life of those who had the benefit of the Revolution. However, over a longer period of time, the advent of agriculture is linked to poorer health, vectors of disease and lower quality of life (in terms of intractable disease). Despite what I have claimed in the past about hunter-gatherer societies, they do have lower or nonexistent rates of the diseases that currently plague our first-world societies. Why do we have such extremely high rates of disease that they don’t?
Contrary to popular belief, agriculture has caused decreases in many facets of our lives. These diseases, more aptly termed ‘diseases of civilization‘ are directly caused by agricultural and societal ways of living. This increases disease rates as it’s easier for diseases to spread faster through bigger populations. Moreover, we haven’t had time to evolve to the current diet we now eat in first-world countries which has lead to what is termed an ‘evolutionary mismatch‘ between genes and environment. We evolved to eat a certain diet and the introduction of easily digestible carbohydrates which spike insulin the highest. Since insulin causes weight gain, and carbohydrate intake has dramatically increased since the 70s, obesity has increased as a result as countries begin to industrialize and more processed foods are available to the populace.
However, since the Industrial Revolution, height has increased along with IQ. Researchers argue that in first-world countries, high rates of obesity are not preventable due to the excess amounts of highly refined and processed foods. There is data for this theory. In first-world countries, the heritability of BMI is between .76 and .85. Since first-world countries are industrialized, we would expect them to hit their ‘genetic height and weight’ along with having the ability to reach their IQ potential. However, with the excess amount of highly processed and refined foods, this would also, in theory, have the population hit their ‘genetic weights’. This is what we see in first-world countries.
To see how first-world, industrialized societies cause these gene-environment mismatches, we can compare the disease acquisition rate—or lack thereof—to that of Europeans eating an industrialized, first-world diet (high in carbohydrates).
In his 2013 book The Story of the Human Body: Evolution, Health, and Disease, Paleoanthropologist Daniel Lieberman talks at length about evolutionary mismatches. The easiest way to think about this is to think about how one evolved to their environment and think how the processes that alter the environment. A perfect example is African farmers. They may dig a trench to divert water to better irrigate their crops, but this then would cause a higher rate of mosquitoes due to the increase in still water and then selection for genes that protect against malaria would be selected for. This is one example of an evolutionary mismatch turning into an advantage for a population. Most mismatch diseases are caused by changes in the environment which change how the body functions. In other words, the current first-world diet is correlated very highly with diseases of civilization and drive most of the mismatch diseases. Most likely, you will die from one of these mismatch diseases.
If you’re born in a hotter environment, you will have more sweat glands than if you were born in a cooler environment. If you grow up eating soft, processed food, your face will be smaller than if you ate harder foods. These are two ways in which ‘cultural evolution’ (cultural change) have an effect on how the human body grows and adapts to certain stimuli based on the environment around it.
The largest cause of the higher disease rate between industrialized peoples and those in hunter-gatherer societies is shifts in life history. As our life spans increased through modernization, so to did our chance of acquiring more diseases. Of course living longer affects how many children you have but it also raises your chances of acquiring an evolutionary mismatch and your chances of dying from one.
Daniel Lieberman writes on page 190 of his book The Story of the Human Body:
A typical hunter-gatherer adult female will manage to collect 2,000 calories a day and a male can hunt between 3,000 and 6,000 calories a day. (24) A hunter-gatherer groups combined efforts yield just enough food to feed small families. In contrast, a household of early Neolithic farmers from Europe using solely manual labor before the invention of the plow could produce an average if 12,800 calories per day over the course of a year, enough to feed families of six. (25) In other words, the first farmers could double their family size.
Thusly, you can see how evolutionary mismatches would occur with the advent of an agricultural diet that we didn’t evolve to be accustomed to. This is one of the biggest examples of the negative effects of agriculture, our inability to adapt quickly to our new diets which then accelerated after the Industrial Revolution. Further, hunter-gatherers will eat anything edible while agricultural societies will largely eat only what they grow. This would have huge implications for farmers if a few pests ruined their crops since they relied on a few crops to survive.
The thing about farming is that as the Agricultural Revolution began, this increased the population size as well as making that population pretty much stable in terms of migrating. This, then, led to higher rates of disease as larger populations foster new kinds of infectious diseases. Large populations didn’t happen until the advent of farming, and with it came the first plagues. The first farming villages were small, but “as the Reverend Malthus pointed out in 1798, even modest increases in a population’s birthrate will cause rapid increases in overall population size in just a few generations.” (Lieberman, 2013: 197) So as even small increases in population size would cause a boom in future generations, which along with it would drive disease acquisition and plagues in that new and stationary society.
Lieberman further writes on pages 199-200:
Not surprisingly, farming ushered in an era of epidemics, including tuberculosis, leprosy, syphilis, plague, smallpox and influenza. (44) This is not to say that hunter-gatherers did not get sick, but before farming, human societies primarily suffered from parasites such as lice, pinworms they acquired from contaminated food, and viruses or bacteria, such as herpes simplex, which they got from contact with mammals. (45) Diseases such as malaria and yaws (the nonvenereal precursor of syphilis) were probably also present among hunter-gatherers, but at much lower rates than in farmers. In fact, epidemics could not exist prior to the Neolithic because hunter-gatherer populations are below one person per square kilometer, which is below the threshold necessary for virulent diseases to spread. Smallpox, for example, is an ancient viral disease that humans apparently acquired from monkeys or rodents (the disease’s origins are unresolved) that was able to spread appreciably until the growth of large, dense settlements. (46)
Moreover, another evolutionary mismatch is the lack of sanitation that comes with stationary societies. Hunter-gatherers could just go and defecate in a bush, whereas with the advent of civilization, waste and refuse began to pile up in the area. As noted above, when farmers clear space for irrigation to plant crops, this introduces mosquitoes into the area which then causes more disease. Furthermore, we have also acquired about 50 diseases from living near animals (Lieberman, 2013: 201). There are more than 100 evolutionary mismatch diseases that agriculture has brought to humanity.
We can compare disease rates of people in industrialized societies and people in modern-day hunter-gatherer societies. In his 2008 book Good Calories, Bad Calories, Gary Taubes documents numerous instances of hunter-gatherer societies that have no to low rates of the same modern diseases that we have:
In 1914, Hoffman himself had surveyed physicians working for the Bureau of Indian Affairs. “Among some 63,000 Indians of all tribes,” he reported, “there occurred only 2 deaths from cancer as medically observed from the year 1914.” (Taubes, 2008: 92)
“There are no known reasons why cancer should not occasionally occur among any race of people, even though it be below the lowest degree of savagery and barbarism,” Hoffman wrote. (Taubes, 2008: 92)
“Granting the practical difficulties of determining with accuracy the causes of death among the non-civilized races, it is nevertheless a safe assumption that the large number of medical missionaries and other trained medical observers, living for years among native races throughout the world, would long ago have provided a substantial basis of fact regarding the frequency of malignant disease among the so-called “uncivilized” races, if cancer were met with among them to anything like the degree common to practically all civilized countries. Quite the contrary, the negative evidence is convincing that in the opinion of qualified medical observers cancer is exceptionally rare among the primitive peoples.” (Taubes, 2008: 92)
These reports, often published in the British Medical Journal, The Lancet or local journals like the East African Medical Journal, would typically include the length of service the author had undergone among the natives, the size of the local native population served by the hospital in question, the size of the local European population, and the number of cancers involved in both. F.P. Fouch, for instance, district surgeon of the Orange Free State in South Africa, reported to the BMJ in 1923 that he had spent six years at a hospital that served fourteen thousand natives. “I never saw a single case of gastric or duodenal ulcer, colitis, appendicitis, or cancer in any form in a native, although these diseases were frequently seen among the white or European population.” (Taubes, 2008: 92)
As a result of these modern processed foods, noted Hoffman, “far-reaching changes in bodily functioning and metabolism are introduced which, extending over many years, are the causes or conditions predisposing to the development of malignant new growths, and in part at least explain the observed increase in cancer death rate of practically all civilized and highly urbanized countries.” (Taubes, 2008: 96)
The preponderance of evidence shows that these people have low rates of disease that are endemic to our societies due to the advent of agriculture. There is one large difference between hunter-gatherer societies and industrialized ones: the type and amount of food we eat.
Along with the boom of agriculture, we see a slight decrease in height the longer people live in these types of societies. As the Neolithic began 11,500 years ago, height increased about 1.5 inches for males and slightly less for females. But around 7,500 years ago, stature began to decrease and we began noticing evidence of nutritional stress and skeletal markers of disease. There is evidence that as maize was introduced into eastern Tennessee about 1,000 years ago, a decrease of .87 inches in men and 2.4 inches in women were seen. Further, the height of early farmers in China and Japan decreased by 3.1 inches as rice farming progressed, with similar height decreases being seen in Mesoamerica in men (2.2 inches) and women (3.1 inches).
Anti-hereditarian Jared Diamond asks the question “Was farming worth it?” in which he writes:
With agriculture came the gross social and sexual inequality, the disease and despotism, that curse our existence.
The first two things he brings up are pretty Marxist in nature, though they are true. He implies that agriculture causes so-called ‘sexual inequalities’ in which women are made ‘beasts of burden’, made to do the work while men walk by ’empty handed’. This seems to be one negative to a society that is, supposedly, smarter than Europeans.
Regular readers may remember me criticizing Andrew Anglin and his stance on the paleo diet—with how it’s ‘how European man evolved to eat’. However, I am a data-driven person and I try to not let any bias get involved in my thought processes. I know do believe that we should eat a diet that closely mimics our hunter-gatherer ancestors, though we shouldn’t go overboard like certain people in the paleo community, we should be mindful of the quality of food we do it as we will greatly increase our life expectancy along with our quality of life. Indeed, researchers have proposed that we should adopt diets that are close in composition to what our hunter-gatherer ancestors ate in order to battle diseases of civilization. Based on what I’ve read over the past few months, I am inclined to agree. Indeed, evidence for this is seen in a sample of ten Australian Aborigines who were introduced back to their traditional lifestyle (O’Dea, 1984). In a 7 week period, they showed improvement in carbohydrate and lipid metabolism, effectively becoming diabetes-free in almost 2 months.
In sum, there were obviously both positive and negative effects on human life due to the advent of agriculture (leaning more towards negative). These range from diseases to increased population size, to ‘social inequalities’ to higher rates of obesity (this evolutionary mismatch will be extensively covered in the future) to a whole myriad of other diseases. These then lower the quality of life of the individual inflicted. However, the rates of these diseases are low to non-existent in hunter-gatherer societies due to them being nomadic and eating more plentiful foods. Agricultural societies become dependent on a few staple crops so when an endemic occurs, there is mass death since they do not know how to subsist on anything but what they have become accustomed to. The advent of agriculture leads to a decrease in stature as well as brain size. Further, agriculture and the processed foods that came with it caused us to become more susceptible to obesity, which was further exacerbated by the industrial revolutions and the ‘nutritional guidelines’ of the 60s and 70s that led to higher rates of coronary heart disease. It is the lifestyle change from agriculture that we have not adapted to yet that causes disease these diseases of civilization that shorten our life expectancies. I do now believe that all people should eat a diet as close to hunter-gatherer diet as possible, as that’s what the preponderance of evidence shows.
By the way, to my knowledge, contrary to what The Alternative Hypothesis says, there are no differences in carbohydrate metabolism between races (save for a few populations such as the Pima).