This blog is about the intersection between evolutionary biology and food. But also about practical applications, sustainable agriculture, and general tasty things.
When humans started transitioning towards agrarian ways of life around 10,000 years ago, it wasn't just the types of food that changed. It wasn't just about more reliance on grains and less on meat, but about a fundamental change in the food system. True hunter-gatherers literally live day to day, not storing any food for later use. Horticulturalists started manipulating the forest so that they could have living stores of certain things like cassava and also started fermenting various plant and animal foods. As the human species moved into the arctic (LATER ON in our evolutionary history, contrary to some polar pushers that are popular "paleo diet" authors) and started living in more marginal areas in general, we developed smoking and salting as methods of preservation.*
But with agrarianism came the widespread processing and long-term storage of foods, particularly grains and legumes.
This opened up humans to all kinds of new vulnerabilities from rancidity, molds, and bacterial contamination during storage. We've largely forgotten about these things because science has eliminated so many extreme acute examples. When was the last time you heard about someone getting ergotism? Ergotism is caused by a fungus that grows on rye. In the past, a contaminated harvest could terrorize entire towns. A lovely description from 857: "a Great plague of swollen blisters consumed the people by a loathsome rot, so that their limbs were loosened and fell off before death."
While antinutrients and rouge plant proteins tend to get a lot of focus in blaming such foods for the poor health of ancient agrarian populations, such contamination also probably played a role. In developing countries, aflatoxins, a type of mycotoxins, still remain a serious health issue. They are something to always be aware of when parsing epidemiological data from agrarian cultures.
While few people in the US seem to be suffering from gangrene because of mold, whether or not even low levels of contamination and rancidity are an issue remains debatable. Regulatory agencies have different standards for what is spoiled. In Europe, the standard for Patulin, a toxin produced by P. expansum that shows immune system damage in animal products, is 10 μg/kg for children's apple juice. The action level for the US FDA is 50 µg/kg.
In terms of rancidity, I notice a lot of industrial food producers are adding antioxidants like Vitamin E to oils vulnerable to oxidative damage, so someone is aware that it's a bad thing. But I think a lot of restaurants even exhaust the antioxidant additive's abilities by using the oil to fry stuff over and over again. In animal models at least, feeding oxidized fat is a great way to induce inflammation. There is mounting evidence they are a health threat for humans.
And possibly because such types of spoilage is relatively evolutionarily novel, most humans seem to be unable to detect it simply by taste or smell. This is made worse when one is used to consuming sub-par food. The Chicago Tribute today had an article that noted that many immigrants find US peanut butter tastes rancid, but to most of us it tastes delicious. Also a study showed that 44% of Americans actually preferred the taste of rancid olive oil.
Many people I've talked to report that they feel fine eating "bad" foods in Europe. I've had that experience myself and it's very interesting. It's perhaps a testament to the EU's higher standards.
When I think about the diet I eat now vs. the diet I ate in the past, one thing that stands out is that almost all of my food is now in the fridge or freezer rather than in my cabinets. My cabinets are actually just full of tea and underused ktichen appliances. Of course, solve one problem and another one pops up- there is a hypothesis that Crohns could be caused by bacteria that thrive in fridge temperatures.
*which have their own particular health risks that could make up an entire post
SG: The Pima were first contacted in 1539 by the Spanish, who apparently found them to be lean and healthy. At the time, they were eating a high-carbohydrate, low-fat diet based on corn, beans, starchy squash, and a modest amount of gathered animal and plant foods from the forest and rivers in the area. In 1869, the Gila river went dry for the first time, and 1886 was the last year water flowed onto their land, due to upstream river diversion by settlers. They suffered famine, and were rescued by government rations consisting of white flour, sugar, lard, canned meats, salt and other canned and processed goods. They subsequently became obese. Their diet consisted mostly of bread cooked in lard, sweetened beverages and canned goods, and they also suddenly had salt. I don't see why that's incompatible with the food reward hypothesis. It is, however, difficult to reconcile with the carbohydrate hypothesis.
I've known about the Pima story for a long time, mainly through the work of Gary Nabhan, who wrote Why Some Like it Hot and several other excellent books. Why Some Like it Hot is particularly relevant here because it posits that certain cultures are uniquely adapted to the foods of their own locality and history. That's a far stretch from the typical paleo proposition that we are all adapted to the same foods we ate 40,000 years ago.
It is interesting to note that at around the same time that flour was making the Pima overweight and diabetic, processed foods were harming other populations in other ways. Nutrition and Physical Degeneration has plenty of pictures of toothless children suffering from TB, but almost none of them are fat. Obesity came to places like Scotland only after the advent of processed foods 2.0, the hyperpalatable junk food engineered in laboratories. Why did the Pima get fat so quickly and before these foods were in the marketplace?
The tragedy of the Pima has been a boon for research into the genetics of diabetes and obesity since they tend towards genetic homogeneity. Through this research, several genes have been identified that are linked to their conditions. These include variants in interleukin 6, uncoupling protein, mannose binding lectin, and the leptin receptor gene, to name but a very few of the promising candidates.
So do these genes doom the Pima? Obviously not. There are a few prominent bloggers who say that whether or not you have diabetes is genetically determined and you cannot eat yourself diabetic. This is nonsense.
The Mexican Pima still live as traditional farmers and ranchers, so they are much more active. They are not skinny, but they are not obese either. What is their diet like? Beans, wheat flour (OMG), corn tortillas, and potatoes are the main staple. They eat much less fat than the US Pima. It was only recently that roads came to their area, so needless to say, they don't eat fast food (at least at the time that paper was written).
I have little doubt that their diet was probably much healthier in the past. Pictures of the Pima in the past show them as being svelte. Staples of this older diet included more unusual desert foods such as tepary beans, mesquite pods, acorns, and heritage varieties of corn. One main point of Nabhan's book is that not all plants of the same species or type are made alike. Different beans have different nutritional properties and phytochemicals. The ancient Pima ate both wild and domesticated legumes. Their diet was around 70% carbohydrates.
Even those Indians who still rely heavily on beans and corn are today consuming varieties that have little or none of the nutritive advantages found in the staples of their historic diet. For example, the sweet corn familiar to Americans contains rapidly digested starches and sugars, which raise sugar levels in the blood, while the hominy-type corn of the traditional Indian diet has little sugar and mostly starch that is slowly digested.
Similarly, the pinto beans that the Federal Government now gives to the Indians (along with lard, refined wheat flour, sugar, coffee and processed cereals) are far more rapidly digested than the tepary beans the Tohono O'odham once depended upon. Indeed, their former tribal name is a distorted version of the Indian word meaning "the Bean People."
When Earl Ray, a Pima Indian who lives near Phoenix, switched to a more traditional native diet of mesquite meal, tepary beans, cholla buds and chaparral tea, he dropped from 239 pounds to less than 150 and brought his severe diabetes under control without medication. In a federally financed study of 11 Indian volunteers predisposed to diabetes, a diet of native food rich in fiber and complex carbohydrates kept blood sugar levels on an even keel and increased the effectiveness of insulin. When he switched back to a low-fiber "convenience-market diet" containing the same number of calories, the volunteers' blood sensitivity to insulin declined.
An overlooked aspect here might be social effects. Obesity in the Pima has been tied to the use of formula. It has been also seen that "non-working" Pima women are more likely to consume traditional foods and feed them to their family than "working" Pima women. I put working in quotation marks because I am referring to work in the extractive capitalist sense. It's clear that Pima women have always worked as gatherers and farmers, I'm talking about work that provides only money to the home, rather than providing income of a more holistic sort.
What is fascinating to me is that the Pima have a lower than expected incidence of heart disease. It's clear to me that the Pima are a genetically distinct population with unique adaptations to their ancient diet and lifestyle. They don't show that carbohydrates per-se cause obesity. They do provide an example of the synergistic effects of genes, diet, and lifestyle. If I were Pima, I would be inclined to eating a low-fat high-fiber diet rich in these traditional foods.
But I'm not.
Love trashy clipart.
So let's recap: Tim is saying legumes are an essential part of his healthy slow carb regimen. Many paleo authors say that legumes are pretty much the devil.
I say: they are a completely inessential food that may contribute to health problems. It's never been shown they cause them in healthy adults, but biochemically there is some evidence that perhaps they could exacerbate some autoimmune disorders. So maybe if you have IBD, avoid them. But if you are a healthy happy adult and your mom offers you a delicious steaming warm Cassoulet filled with delicious duck and foie gras sausage, white beans, bacon, and duck confit... you are an absolute fool if you turn it down.
Official (but incomplete) list of things I don't view as part of a healthy diet, but they aren't going to kill you if you are already healthy and I'll never turn them down if you give them to me and sometimes I order them in restaurants:
Warm lentils cooked in pork belly
Peppermint Ice Cream
Ethiopian spiced lentils
Homemade tortillas cooked in lard
Peanut butter fudge
Jokai (THE BEST hungarian soup that has ham hock and beans)
Polenta with ample amounts of cheese
Grandma's grits with butter and tabasco
But you'll never find me chowing down on some lame canned beans in the name of health. Also, I turn down anything with gluten since the health effects for me are so acute.
As for sex tips since I criticized Tim's sex chapter, I won't give them on a blog that my family reads :) But suffice to say, if a guy did them method Tim advises to me I would have to slap him. I am a woman (in case you didn't notice) and I've talked about orgasm a lot with female friends. All women are different. You're going to have to invest time in a woman to really find out her secrets.
As for me being bitter about single shiftless men, this is not because I've dated them :) It's because sometimes I get treated like a coat rack for some reason and I get to hear lecherous stories from the world of pickup. At least I now know what men to avoid! Someone said I should be grateful because The Game and whatnot encouraged men to actually talk to women. Um...the sad state of modern men that they have to be told such things from a book.
IGe tests aren't very accurate, apparently. But I wonder if the presence of "benign" antibodies is really so benign. Maybe it means that the gut permeability is too high. Either way, I probably wouldn't feed my children peanut butter. I love love love peanut butter and it's one of the non-paleo foods I truly miss, but peanut production is rife with mold problems from farm to fork and peanut butter is very high probably rancid PUFAS. I wonder if peanuts cause increased gut permeability that also leads to other allergies as inappropriate food constituents are allowed into the blood stream. Many people I know who are allergic to peanuts are allergic to otherwise harmless foods like shellfish. Of course I don't know that many people allergic to peanuts my age. Growing up, we didn't have special "peanut free" tables, but you'd be loathe to find a school without one these days. What things have changed? I ate crappy sugar-filled things growing up, but maybe it's because things are now full of gut-irritating white "whole" wheat.
Unfortuantely, I don't think these researchers are wondering about that. Their "happy ending":
The only way to determine whether Ellie was truly allergic was with a food challenge, which she finally passed last October. Ellie now enjoys kid-favorite peanut butter candy, crackers and granola bars. The family was able to ditch the epinephrine injections kept in case of emergency. Said Kampwerth, "It's a big relief."
Wow, what a relief that their child can enjoy sugar-loaded processed junk!
If you want to see some beautiful photos of traditional fish eating in a Gwich'in camp, look here, though keep in mind that at the time these pictures were taken, this tribe was eating modern foods.
Lately health blogger Matt Stone has been creating a bit of a controversy in paleo circles by blaming thyroid issues on low carbing. There is no question that many long term low carbers and paleo dieters suffer from thyroid issues . Why? Arctic cultures like the Inuit, Koyoukon, Yupik, Sami, and many others have a traditional diet that is very low in carbohydrates. Many people have written about how healthy they are despite following a diet that's not exactly the USDA food pyramid.
I think it's pretty clear that the problems people are having are not due to a lack of cornbread. What all the healthy arctic people had in common was that they consumed a wealth of marine foods ranging from seal liver to seaweed. Marine foods have nutrients all of us could benefit from. Traditional cultures not only ate fish, they ate whole fish: fish eyes, liver, and bones. This stuff is a hard sell to those of us who grew up eating the typical American diet, but it's definitely worth getting used to eating, as the arctic explorers did.
Until I was twenty seven I had the belief about myself that I could not eat fish and felt certain that its taste was obnoxious to me. I thought it an interesting peculiarity and assumed that everyone else would think so and there were few things I told about so often as the fact that I was peculiar in that I could not eat fish. I think I might have lost the notion sooner if it had not formed such an excellent topic of conversation
I've said it many times: if your paleo or low carb diet is a bunch of ground meat and some chicken breasts, you probably need to rethink things. As far as the carb controversy, it's a rather old one. The Weston A. Price Foundation has been criticizing the paleo diet for not including traditional dairy and fermented grain/legume products. In his books food ecologist Gary Nabhan recounts how Native American tribes like the Pima never suffered from obesity on their traditional high carb diet. Born To Run recounts the impressive athletic fears of the corn-loving Tarahumara tribe. The yam eating Kitavans don't have too many problems either.
But the paleo diet is about more than just not being obese. Plenty of people follow it to heal from autoimmune conditions and damage from eating the Standard American Diet. Others follow it to improve athletic performance. The truth is that while traditional agrarian cultures didn't have type II diabetes epidemics, the healthiest bones that anthropologists have found were those of coastal foragers. As Dr. Kurt Harris says "tolerated is not optimal."