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A Cultural History of Fat (historytoday.com)
78 points by whocansay 26 days ago | hide | past | web | favorite | 70 comments

A company that produces food that is more appetizing and less filling than its competitors will sell more of it and beat them in terms of revenue and profit. They either have to align themselves or die/be assimilated.

Even without any ill intent, growth seeking in the food industry would have lead to an obesity epidemics.


If I eat a snickers bar and afterwards I'm still hungry, I'm not necessarily going to eat another snickers bar. If I eat a very flavorful salad but perhaps am not feeling quite satiated, next time I'm not necessarily going to order the competitor's product that is drenched in olive oil.

I'm sure there is some truth to these sorts of "survival of the fittest" arguments, but you can only simplify how people reason about food or how they consciously or subconsciously decide what to eat so much before it becomes a parody of itself.

So you agree with me, but still want to ridicule my argument ("parody of itself")? I'm also quite surprised to see a statistician use anecdata as arguments.

Humans are predictably irrational, there are mountains of scientific evidence on the topic [0, 1].

The industry plays us like fiddles to get us to consume ever more. There are more parameters than the ones I described above (socialization and long term hormonal effects come to mind), but the growth of the food industry is the main driver behind the obesity epidemics.

All that food has to be bought, otherwise there's no growth, and investors are not happy and they put their money elsewhere.

The easiest way to convince people to buy food is to make them want to eat it. Modern food has been engineered and optimized to be deceptive and take advantage of our instinctive and cognitive biases, in order to get us to eat more than we need to be healthy.

0. https://web.mit.edu/ariely/www/MIT/

1. https://www.amazon.com/Influence-Psychology-Persuasion-Rober...

For all these market forces that are making profits off addictions it is interesting to see how they manage to get away with it in public perception by addressing personal responsibility - while their products are engineered to induce addictions and diminish will power.

I found this study about the tobacco industry's use of the personal responsibility rhetoric: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4318333/

Coca Cola and Nutella seem to do a lot of advertising through sports. They are like parasites living off the idea of rationality and personal responsibility that humans need to live a successful, self-determined life.

I'm not claiming that personal responsibility is no factor here, but it would be just as wrong (and pretty bad for the affected people's mental health) to assume it is the only one.

The fantasy that humans have unbridled free will is both pervasive and highly toxic.

It conveniently ignores piles of neuropsychological studies on the topic and it is also used to justify "tough on crime" policies that do more harm than good.

I'll put it aletrnatively:

Since 1) we eat too much and 2) we're not being force-fed, what drives the food down our collective throats?

How do you explain the obesity epidemics which is a very recent phenomenon, if not through perverse market forces?

> How do you explain the obesity epidemics which is a very recent phenomenon, if not through perverse market forces?

- Extremely high levels of food security in developed nations. It's hard to get fat when food isn't available.

- Related, nutritionally-questionable food products that were used to achieve this food security (primarily mass-preserved and processed foods).

- A transition from jobs requiring large amounts of physical labor to those that require little or none.

That's just what I can think of off the top of my head. Like most societal problems, the causes are myriad and complex.

From an evolutionary standpoint, less eating restraint may be linked to increased survival rares in times of scarcity, as stored energy in fat provides a clear advantage. Nowadays, in first world countries, food is everywhere and "overeating" becomes much easier.

Additives for food security is an intetrsting angle, thanks. That being said, I'm not convinced that it requires making fattening products, but it was in part the outcome.

Your last point is at least partially mitigated by the fact that food intake regulation factors in physical activity in most people.

Laziness. Supermarkets still sell raw food (vegetables, meat, etc) that can be used for cooking. But it takes time and effort to do it (+washing) so buying already made but unhealthy dishes is appealing for a lot of people.

But why are the ready made meals unhealthy? It’s not because they’re ready made rather than fresh cooked.

Ready made meals are usually higher in sodium and fats than fresh cooked meals.

Edit - https://www.consumerreports.org/food-shopping/supermarket-pr... The article doesn't call out higher amounts of fat in prepared food, but does mention higher cost and added preservatives.

I don't know the exact reasons why, but food made in large batches tends to be less tasty than food made in smaller batches at home. if the food is made in large batches and it's not fresh, it takes another "tastiness" penalty. adding excessive fat and/or salt is an easy hack to make ready made meals a bit more palatable.

I suspect it would be very difficult (ie expensive) to make ready made meals anywhere near as appealing as home cooked without using these tricks.

That explains why we buy ready-made meals, but not why we buy unhealthy rather than healthy ones.

"Laziness" - non-explanation word is not an explanation.

>How do you explain the obesity epidemics which is a very recent phenomenon, if not through perverse market forces?

When you put it that way, I feel like asking how could the obesity epidemic possibly be blamed on perverse market forces? It's not like the food markets of the past were any less competitive, greedy or unregulated than they were when the obesity epidemic took hold.

I will weakly float two hypotheses that I've heard to explain it: technological change that made certain types of food cheaper (the bad ones), and government regulation that subsidized corn production which of course subsidized corn syrup based foods.

You are correct that the market forces were there before, and that the epidemics couldn't have occurred without industrial food transformation. Before that, how fattening food was was limited by biology and I suppose that it was slow enough for human populations to adapt.

Also, the "artificial = good" meme mid-20th century probably helped bootstrap the whole thing by disrupting otherwise conservative feeding habits.

Corn syrup is a positive factor, but the obesity epidemics also occurred in other industrialized countries where it is far less prevalent.

Thus the driving force is growth seeking beyond reason (through both the market and (corrupt?) subsidies). Technology just gave it leverage.

Sure you are. Are you buying an individual snickers bar or a 5 lb bag of Mars, Inc confections?

Also, the use case and marketing strategy for your two scenarios are different. A product like Snickers is a quick on-the-go fix of food. The marketing connection for a salad is different -- the money and full feeling is in the dressing. Many people translate "salad" as leaves with goops of fat/sugar on them. If you are a oil/vinegar person, you're an awful customer for Kraft.

The food industry is attacking traditional, lower margin foods to make more $. The best example is the push against milk in favor of nut and grain based white liquid. All of the substitute products are mostly water and corn syrup, but are sold at dairy prices.

A lot of plant milks are unsweetened, and there is a high and growing demand for these products—yes these companies want to make money, but it's not as if they were manufacturing the demand, they're merely capitalizing upon it.

Better yet is to make one's own oat milk; I agree that they're exorbitantly expensive, albeit (here in the US) the dairy industry is immensely subsidized and so we consumers don't see the true cost of our cow's milk.

Subsidies for milk benefit processors, not producers. Producers today are going bankrupt left and right as they are forced to sell at fixed prices unless they go direct to consumer.

It's all the same problem. Allowing a cartel of dairy processors to control to production and delivery of dairy products is equivalent to allowing a cartel of producers (in the case of almonds) and big food is the same.

All benefit from extensive subsidy (that corn syrup isn't market-based), with the added risk of food security issues, especially for nut milks that are exclusively sourced from a few counties in California.

Oh, I was bringing up the price in comparison to the price of plant milks from a consumer's standpoint—while plant milks seemingly have a high markup from raw materials to product (transportation and storage costs aside), our perception of what makes it expensive has an unrealistic anchor in the subsidized cost of cow's milk. Paying $12 for a gallon of cow's milk vs. $5 for a gallon of oat milk changes the picture a bit.

I get your point, but it's much more complex than that.

Leaving aside the issues with directly comparing plant milk with actual milk, the economics are not what you lay out. Oat milk is really yet another industrial corn product. The caloric content isn't cloudy stuff squeezed into water, it's fructose from corn. In the quest for price stability, corn subsidy is one of the main knobs used by USDA from a subsidy and policy standpoint.

I haven't done a deep analysis of this, but I do buy milk from a farm with a smallish herd and a direct-to-producer model that allows the farmer to actually operate his own dairy and sell milk at a profit. Even with the small scale of the operation, milk costs about $6/gallon. When you buy milk from a scaled dairy operation, the economies of scale are massive... you have 1-2 processing plants handling the milk of tens of thousands of cows.

The plant milk phenomenon is all about allowing massive agribusiness to take over a big product category that has remained regional.

> Oat milk is really yet another industrial corn product. The caloric content isn't cloudy stuff squeezed into water, it's fructose from corn.

This is just factually untrue. Here's the ingredients for the most popular oat milk brands, found from a Google search:

1. Oatly: Oat base (water, oats 10%), rapeseed oil, calcium carbonate, calcium phosphates, iodised salt, vitamins (D2, riboflavin and B12).

2. Califia: Oatmilk (Water, Oats), Sunflower Oil, Minerals (Dipotassium Phosphate, Calcium Carbonate, Tricalcium Phosphate), Sea Salt


4. Silk Oat Yeah: Oatmilk (Filtered Water, Oat Extract), 2% or less of: Sunflower Oil, Vitamin and Mineral Blend (Calcium Carbonate, Vitamin A Palmitate, Vitamin D2, Riboflavin (B2), Vitamin B12), Malt Extract, Dipotassium Phosphate, Gellan Gum, Sea Salt, Sunflower Lecithin, Locust Bean Gum, Ascorbic Acid (to protect freshness).

None of these have corn syrup or added fructose.

> The plant milk phenomenon is all about allowing massive agribusiness to take over a big product category that has remained regional.

You don't need plant milk for that. For proof just see Fairlife, the Coca-Cola Company's attempt to turn milk into a branded good.

I think marketing plays a huge role here. Being told again and again that you "need/want" it might act on your subconscious at one point.

And people tend to trust the marketing and the big text on the label more than anything sometimes. The label says it's healthier, that promo on TV said cool young people consume it, etc. So you won't stop to "objectively" evaluate the product. Many blind tests for products turned over results that were completely the opposite of what the market was saying via sales numbers. Because without the label and the marketing driving the decision people had to fail back to good old fashioned taste (ex: this tastes better) and common sense (ex: this offers more for the same taste / price).

When a person is struggling to even pay his bills, which most of the Americans are, then tactics like these from food companies does have lots on influence on what such people decides to eat.

Maybe not in the individual instance, but in the aggregate, sure you will.

Humans eat foods that reward them, because that's how dopamine works. We've figured out how to optimize the rewards, too: Salt. Fat. Sugar.


I find "appetising" and "less filling" are understatements.

When I think of the food industry, I tend to think more in terms of "behaviour reinforcement" and "psycho- and physiological addiction".

I'd even say 'brain damage'. Processed food industry seriously limits what you will taste. Most natural fruits/vegetables have so much variety and subtlety in flavour.. they also often come with built-in satiety triggers. You rarely consume as much salad/carrots than pringles/cookies. Modern life is pretty toxic in the end.

I wouldn't go as far as damage, because it is reversible. If you stay away from saturated stimuli you relearn to taste subtler nuances.

Capsaicin, and similar substances (TRPV1 agonists) which are found in hot peppers and ginger do kill nociceptive neurons, but that's AFAIK the only case where some food directly damages your nervous system.

I think food addiction is mostly reversible (it may be easier to relapse than to become addicted in the first place).

Yeah I hyperboled on purpose. It's mind boggling how industrial societies are "deceiving people".

That's where "ill intent" kicks in.

Too much focus on growth is a quality that always leads to once doom whether its a person or a corporation. Its sad that our business economics favors this.

The top earners are addicted to easy return on investment and can't envision a world where they can't rely on growth to deepen their pockets.

Given their already tremendous wealth, they are powerful enough to brainwash the rest of us into helping them (hence the song above).

This article does not discuss in depth the change in diet from mainly protein and fat based diets of the hunter-gatherers to carb-rich diet of today.

Were all hunter-gatherer diets protein and fat based? https://www.scientificamerican.com/media/inline/paleo-diet-h...

Is that percentage by weight, percentage by dry weight, percentage by calories, or something else?

And no matter which I interpret it as, all those diets are "protein and fat based" by Standard American Diet standards. Seeds and nuts are very high in fat.

This specific graphic seems to be by weight. The type of meats the Inuits eat is really high in fat.

We've had a carb rich diet since the neolithic revolution.

The obesity epidemics started after WW2.

I don't think that they are related.

> We've had a carb rich diet since the neolithic revolution.

This isn't true.

The modern diet gets 90% (asspulled number, sorry) of its energy from sugar, white flour and potatoes.

None of these three really existed in any measurable quantities three hundred years ago.

Sugar especially is something only very modern people started to eat in huge quantities.

Bread was the staple food for most of that period. GP was contrasting modern and paleo diet.

It would be wiser to contrast 1918 with 2018 (and I agree with you that refined sugar and starch are most likely involved in the current mess).

> Bread was the staple food for most of that period.

No, not really. The refined white flour we eat today basically didn't exist until very recently.

Their bread wasn't like our bread. It was coarsely-ground and made of bran, barley and rye. Compared to what we eat today, it had much higher fiber content and more fat. It would have been much harder for our ancestors to mainline pure carbohydrates by eating bread like we do.

Carbs in themselves aren't so bad, but the problem is that your body won't ever be sated by eating carbohydrates. (Kids around Halloween will attest.) Eating pure carbs is a very bad idea.

I never said it was white bread... Besides, I agree with the rest of your comment.

I'm not sure potatoes are the problem.

The problem is carbs give you short term energy. It's great and healthy if you're doing manual labor, playing sports, lifting weights, etc. or otherwise burning that caloric intake.

If you're watching TV and eating carbs your energy boost is wasted and can get stored as fat.

And sugar as far as far as I'm aware is never healthy but can have less of a health impact in very small doses.

Yeah, I begin to wonder if we need to be a little more specific when talking about this, e.g. not just "carbs" but "simple carbs" and "complex carbs", or "refined" & "unrefined". We've dealt with this once before with saturated & unsaturated fats, vs trans fats.

Carbs are carbs. The biggest problem is that you won't feel full or know when to stop if you're eating just carbs. You need fats or fibers to stop eating, hence "unrefined".

Also physical activity for most people took a nosedive in the past decades. Work has mostly shifted to static jobs and that shifts the balance of any diet.

The carbs we get now in modern processed foods are not the same carbs we've been used to for millenia.

Please tell me more ? At which level ? Genuinely interested :) !

Carbohydrates used to come from fruits (with fiber), vegetables (in small amounts & with fiber), and starchy vegetables (starches are complex & slow to digest). Today, carbohydrates are consumed in simpler forms and refined to be more concentrated.

In the former case, they digest slowly. In the latter case, they digest quickly. The practical implications of this are immediately obvious if you have ever heard of glycemic index and glycemic load, but in short, fast digestion & large quantities results in a big spike in blood sugar which is hard on your body & leads to diabetes.

Also important is that the original forms of carbohydrates came with all kinds of other nutrients. A sweet potato includes vitamin A, vitamin C, manganese, copper, pantothenic acid, vitamin B6, potassium, niacin, vitamin B1, vitamin B2 and phosphorus. Sugar on the other hand is the quintessential "empty calorie", carrying no vitamins, minerals, only calories.

For one, the amount of refined sugar in our diet exploded recently.

More generally, even if the molecular building blocks didn't change, the way food is prepared industrially and marketed makes us more likely to eat too much of it.

A lot of our modern economy seems to be relying on human predisposition to addictions. Think sugar / carbs, alcohol, tobacco, certain games, news and social media and their recommendation engines. All exploiting similar neural pathways.

Yup. The free market as the end to all means relies on several incorrect assumptions:

1) humans are not rational agents that always pursue their best interest

2) local optimization (what the market does) doesn't always lead to a global optimum

3) oftentimes the interest of investors and consumers diverge and the former have far more power (information asymmetry).

In the country I live in, white flour must legally be mixed with iron. In natural foods, iron is bounds to proteins like hemoglobin or ferritin. Legally mandated iron is just "iron", which means whatever's cheapest, i.e. metallic iron powder. This is known to be poorly absorbed:


So what happens to the non-absorbed portion? I have read speculation that it could affect intestinal bacteria. Intestinal bacteria are poorly understood, but widely believed to affect human health. What happens when you start feeding them evolutionarily novel nutrients? I'm not claiming that it has any measurable effect, good or bad, but from a precautionary principle viewpoint it seems to me a bad idea.

Now we're getting somewhere...

But clearly not frequently enough, hence the obesity...

Government dietary recommendations became politicized in 1980, and increasingly separated from both nutrition science and comprehensibility to the public with each 5-year revision. In 1967, the bacterium used to produce the enzyme that turns corn syrup into high-fructose corn syrup was perfected, and HFCS became available in industry. In 1983, it was confirmed as GRAS status, and started replacing sucrose sugar in foods. The food-industry had already been replacing fats with sugars as a result of popularized science suggesting that higher-fat diets were a causative factor for heart disease.

Purchasing power for below-median wage-earners has stagnated since the 1970s. Lower income levels correlate with higher obesity.

Climate-controlled buildings are now the norm. More efficient heaters and coolers make it cheaper to be in a 20 degree C environment year round. Clement climate correlates geographically with higher obesity.

Canine Distemper Virus has been shown (Lyons, 1982) to cause permanently-elevated levels of obesity in mice. Since then, other infectious diseases have been found to promote obesity in animals: RAV-7, Borna, Scrapie, SMAM-1, Ad-36, Ad-5, Ad-37. Gut parasites produced symptoms similar to metabolic syndrome in dragonflies. Obese humans have been found to have a 3 times higher incidence of evidence of past infection by adenovirus Ad-36 than the non-obese (30% vs. 11%). If twin studies, where one twin had been infected by Ad-36, and the other not, the exposed twin was fatter. Across all studies, evidence of past infection by Ad-36 always correlated with a fatter subject, with causative significance. It even works with viruses originating in nonhuman animals, that do not otherwise cause visible symptoms. A sick bird could make you fat, without ever making you sneeze.

Analyses of digestive tract microbiotic factors have discovered causative significance for obesity in some factors. Experimental fecal transplants have resulted in changes in the recipient's weight and body composition.

Studies of epigenetic DNA methylation, sibling genetics, and maternal weight suggest that children of obese mothers may have greater predisposition to obesity, creating an intergenerational feedback loop. Fat mothers make fat daughters make fat granddaughters. This could be experimentally verified by cloning/twinning a female animal embryo, applying different environmental factors to produce breeding animals of different obesity levels, and implanting each with a second set of clone embryos. The second set of clones would then be kept under identical environmental conditions. Unfortunately, cloning processes themselves introduce epigenetic regulations and deregulations that ultimately result in obesity. Cloned mice get fatter when they get older.

It seems as though older mothers bear children that grow fatter as adults. Children of moms over 30 have higher body fat percentages than children of moms under 25, by about 2.7 percentage points. Both low-birthweight and high-birthweight babies correlate to greater adult obesity, and older mothers are less likely to have middle-birthweight babies.

Sleep deprivation correlates with higher obesity.

In short:

  change in foods composition   \\\
  wage stagnation                \\\
  literal adenovirus epidemics    \\\
  change in gut microbiota         \\\   OBESITY
  intergenerational epigenetics    /// (complex cause)
  delay in child-rearing ages     ///
  chronic sleep deprivation      ///
  other factors???              ///

Lots of correlates, Let's untangle that a bit...

- Poverty can't be causal here, since it doesn't match either the timing nor the geography of the epidemics.

- Intergenerational epigenetics is a secondary factor, but it can't be causative in the first generation.

- While the adenovirus study is interesting I'd be surprised its spread mapped with the time/space patterns of the obesity epidemics worldwide.

I mention geographical spread because the epidemics seems to spread along with industrialization, e.g. urban China is affected, while rural China isn't (yet?). The spread of the epidemics seems to map well with the spread of Western junk food. The following parameters could somehow make sense if Japanese folks weren't so lean

- delay in child rearing (where the effect size is minor)

- chronic sleep deprivation (and wow, 1/3 US adults sleeps less than 6 hours per night whereas 1/3 gets more than 8 hours).

- Microbiota is interesting, but known to be influenced by diet. So a problematic microbiota could be a maladaptative change consecutive to a bad diet, that perpetuates the issue.

These factors also apply to Japan, which has resisted the junk food onslaught for cultural reasons. Japan has ~3% of obese folks, and that was the case before they started aggressively monitoring belly fat in middle aged folks. Japanese folks who migrate to the US and adopt the local diet grow fat, so the difference isn't genetic.


This leaves us with food composition and marketing as the main causal factors.

- Why can't poverty be causal? An essential part of food composition and marketing is price. As your disposable income decreases, the composition of items on the McDonald's value menu becomes more relevant to you, and the quality of the produce at Whole Foods markedly less so.

- Intergenerational epigenetic influence means that factors that are no longer overtly visible may have a lasting effect. If, for example, leaded gasoline exhaust fumes made grandma fat, that contributory cause could then invisibly propagate to a later generation via epigenetic regulation attached to gametes and occurring in utero.

- In 2011, someone suggested that Ad-26 and Ad-35 be used in an Ebola vaccine, to work around preexisting Ad-5 immunity in targeted populations. The anti-vaxxer nonsense notwithstanding, the hypothesis that an unknown obesity vector has been spread via routine vaccination, without any other adverse symptoms or side effects, has not yet been tested. Better fat than dead, though.

Several hypotheses regarding decrease in dietary quality have been tested, and found to be unsupported by evidence. The corn lobby has quite a vested interest in proving that HFCS is not significantly different from cane sugar sucrose in prepared foods, so you can find a lot of very narrow studies comparing HFCS to sucrose that all conclude they are the same dietarily, without going anywhere near price, or politics, or comparisons with the fats that both sucrose and HFCS have been replacing over the years. I foresee future studies declaring (cheap) palm oil to be dietarily equivalent to other (more expensive) oils, without ever noting the impact of prices on recipes and diets. Broader studies likely have a harder time getting funding.

Microbiota are also influenced by location--even temporary changes in location. Montezuma's Revenge and Delhi Belly and trail trots can all cause rapid change in one's gut constitution.

Observing Japanese who migrate to the US and preserve their previous diet could be elucidative. If they don't change anything about their lives other than their location, would they grow fatter?

> - Why can't poverty be causal?

Because most poor people around the world are not fat and have never been until recently. In the countries affected by the obesity epidemics, it may be causal, but it doesn't explain why obesity struck somewhere and not elsewhere.

> - Intergenerational epigenetic influence means that factors that are no longer overtly visible may have a lasting effect.

Agreed 100%, it has an impact in the long run, but as a secondary factor, not as a trigger.

> - vaccines

I don't understand the point you're tying to make (beside "fuck anti-vaxxers", and I couldn't agree more). Specifically, I don't understand the link between these specific anti-Ebola vaccines and the possibility that vaccines could cause obesity.

> - HFCS...

A high fructose diet causes non-alcoholic fatty liver disease (a close cousin of metabolic syndrome), and that is well established. In general I have little trust studies that are privately funded. Too much room for bias.

IIRC the Japanese who migrate and keep their traditional diet don't grow fat. This is purely out of memory though, from something I read or heard a long time ago, and I could be wrong.

In vaccines, viruses that are related to the target virus that present similar external structures may be used to train the immune system to target those structures. Immunity to the lesser virus confers immunity to the dangerous one. The specific suggestion was to change the viruses used in the Ebola vaccine, because too many people already had exposure and immunity to Ad-5. This implies that Ad-5 had been used in an earlier iteration of the vaccine. And Ad-5 is one of the adenoviruses that cause obesity.

Cowpox conferred immunity to smallpox--the similarity that led to the invention of vaccination in the first place.

It might be possible that some routine vaccination employs a virus that has always been considered completely harmless, with no visible symptoms beyond a little soreness and nasal sniffle, and that virus actually causes epigenetic changes that impact appetite and satiety, just like Ad-36, Ad-37, and Ad-5. There are about 50 known human adenoviruses, and less than 10 are believed to cause additional obesity. There are also viruses that are mainly pathogenic in other species, which cause no obvious symptoms whatsoever in humans--and in other species that are not the main host species--other than an increase in body fat. There are a lot of viruses out there. Only a small fraction have been studied extensively. Few would care to fund a test for antibodies to a virus that no one is afraid of, and that's what is needed to establish a correlation between exposure and obesity. The only reason adenoviruses were studied for this at all is because the avian virus that caused chickens to die fatter was denied an import license, and the researcher had to find something else that was already endemic.

Sometimes, a virus can be added as an adjuvant. It doesn't even have a direct impact on the targeted dangerous virus, it just makes the vaccine more effective by stirring up the immune system a little.

So it is entirely possible that vaccines that use live viruses that are traditionally considered harmless have never even tried to evaluate whether those viruses have impact on weight gain 10 to 20 years later. Those kids of anti-vaxxers that somehow survive to middle age might just end up with a lower average BMI than their vaccinated peers. It might be the only way we'd ever know. Usually, people who are not vaccinated live in a completely different culture, that would confound all the variables. An American anti-vaxxer living the same lifestyle (aside from the addled parents) as an immunized American would be a more apt comparison. The only other way to test would be to change the composition of the vaccine (an act that has an ethical impact) and wait a few decades to weigh people and caliper their back fat.

That's fascinating, thanks a lot! I have a medical background, so I was familiar with how vaccination works, but not with the specifics of adenovirus!

Adenoviruses are just scraping the surface, too. We have very little knowledge so far on how viruses, bacteria, fungi, and parasite animals can impact epigenetic regulation and deregulation in ways that are not immediately obvious. And obesity isn't exactly something that shows up in measurable quantities a few days after initial exposure. You wait decades, and the difference attributable to the variable under study might be a 2% difference in body fat. That's something you would only find if you already sort of knew where to look.

We're only finding this stuff now because the problem has grown to the point where researchers are specifically asking "why the heck are we so much fatter now?" They are finding multiple answers.

It turns out that real viruses can hack your body and change your persistent settings, just like software viruses can get into your computer and install a botnet rootkit. Some of those settings aren't even accessible to users. (I know if I had a slider bar to change my own body's preference for fat percentage, I'd drag it to 20% and tap the lock icon.)

Learning about this stuff, I now look at fictional plot devices like the super soldier procedure from "Captain America" in a new way. The machine demethylated all the DNA in Steve's body, and the serum injection targeted some specific genes to be re-regulated. Rather than chopping up the genes as CRISPR/Cas9 would do, an epigenetic regulator nondestructively tuned them, and set up positive feedback loops to keep them tuned to the "maximize Nazi-punching" profile. That's still far beyond our current abilities, but it makes it all seem more plausible.

Tangentially, I remember reading a paper that was linking an auto-immune reaction to some hormone-like protein produced by e. coli and both anorexia and bulimia. Are you familiar with the subject? Has it been confirmed?

Hunter gathers ate whatever they could get, so varied a lot from place to place. As I understand it the Hadza's main source of calories is from tubers, so lots of carbs, just lots of fibre too.

Why should it? You haven't offered any concrete reason for why.

It is a book review. I would expect it to cover whatever the book covers, from whatever angle the book decides to approach things.


They've been replaced with Keto.

"Keto" isn't a myth, it's basic biology and metabolism facts.

How are the cultural metaphors verified, like the connection between focus on the afterlife and fatness attributed to the rise of Christianity in Europe?

I still can't put a handle on how historians are able to determine what a culture's prevailing attitude is toward something when it seems so ephemeral.

This is a slim summation of the contents of a fat book.

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