This blog is about the intersection between evolutionary biology and food. But also about practical applications, sustainable agriculture, and general tasty things.
When people use the contact form on the bottom of this site, maybe they should take a few seconds and think about two things I don't tolerate very well, which are
Maybe don't send me that stuff, because I will post about it, and I will criticize it. Or maybe on the latter case, just leave the historical narrative out of your spiel if you can't waste more than an hour thinking about what it might actually imply.
One thing I really regret is when I first got healthy by eating a paleo diet, I thought that if everyone just ate like me, they could have a slim body like mine. It didn't seem that hard to me. So I became a zealot about it. But that process of being a zealot forced me to talk with a wide range of people about their experiences with food and health- from relatives to people I met at paleo meetups in real life. What shocked me were the people who ate like me, some of them ate "better" than me, and yet they were struggling with their weight. I even met people who gained weight on diets like mine. It was eye-opening.
And then there was the process of me discontinuing my strict diet, once when I moved to Europe, and next after I was having low blood pressure issues. I was talking to a friend who lost a lot of weight on paleo successfully and now works...making pizza. We were both joking how we have worried that we were going to suddenly gain a bunch of weight. But it never happens. It's not like we returned to a junk food diet, but I'm not going to turn down some ice cream or homemade pizza. And yet there are people right now turning down the kinds of things who can't seem to slim down. And then there are are fair number of people who slim down on diets full of paleo demonized foods like legumes and whole grains.
Some of them realize that health is about more than being slim, and while gaining weight might be a bad sign, the fact that they can lose a little and feel healthier is more than satisfying. Others however give up, disenchanted with the promises of a slim figure, dismissing it as just another fad diet.
Recently Jonathan Bailor sent me a contact email not once, but twice with his new "Slim is Simple" video to celebrate the creation of a non-profit devoted to distributing his educational material on healthy eating. I was surprised that so many got excited by this video. I criticized it on Twitter and some people were upset by that, saying it was a great educational tool and we need more such "simple" tools. No reason to be obsessed with scientific accuracy. Now I don't think I have that problem- I have recommended books that are quite imperfect on this blog many times from The Primal Blueprint to The Paleo Solution, but I don't recommend something unless I feel it has a useful and correct core.
Luckily I wasn't the only one who saw right through this video, Beth at Weight Maven, also posted a skeptical take on it. Evelyn has also written about Jonathan's other work before. I won't even get into his questionable calorie math that doesn't seem to bother with the fat that the correct equation takes maintence, which depends on body size, into account.
But I also would love to see more books that simplify eating without bordering on inaccurate propaganda like this video. I felt like I was watching a cult indoctrination film. Not only that, but it would seem its bolsters didn't even notice he's recommending a diet that is pretty different from the one they recommend- a diet based on three pillars of protein, fiber, and water. Eat as much as you want of those three things (maybe it helps that if you eat too much of the first two, you'll get diarrhea).
That's right- have as much protein as you want on this diet, have twice as much as normal, you'll be so satiated you'll supposedly forget about ice cream.I think this is exactly the kind of diet I coined the term "faileo" to describe (though sadly I feel this eventually contributed to a culture that somehow thinks you can guzzle as much coconut oil and bacon fat as you want, when I was kind of just trying to get people on board with more reasonable things like lamb shanks). The language is also exactly what many of us have tried to get away from, like the idea that we are "designed" for certain "clean" (an excessively moralistic word reminiscent of Kellogg and other health puritans) foods. Other foods, like starches and sugars (including most fruit- only citrus and berries are given a pass), will "clog our body."
But then I gets weird, because he says "almost everyone stayed healthy and fit without even trying until very recently" and the visuals for this are very interesting:
So we have an early bipedal ancestor, and than an Egyptian, and Pioneer, and someone who looks like they are from the 40s or 50s. Oh and a rather curvy person, who we presumably don't want to be...if only we knew what those Egyptians did. But Egyptians ate diet rich in bread and beer. Wait, I thought all these foods were the ones the video describes as "unnatural" and are responsible for our modern "clogs"? Hmm, well maybe we'll see about the pioneer woman. American pioneers had access to much more meat and fat than the average Ancient Egyptian, but they also ate things like biscuits and hoe cakes. 40s to the 60s? Well I collect cookbooks from those eras and they are certainly not full of an austere cuisine of protein, fiber, and water. Even if he had used the typical types of people that paleo dieters hold up as examples- the Hadza, The !Kung, the Kitavans, and other modern peoples who still live foraging lifestyles and remain very healthy, it would not make sense, because their diets contain a large amount of starch and even simple sugars.
Another use of history offender is Dr. Lustig in his new book Fat Chance: Beating the Odds Against Sugar, Processed Food, Obesity, and Disease. Others are more qualified to comment on the biochemistry errors in this book, but the food history in this book is so inaccurate that I wonder if publishers even bother to employ fact-checkers any more. His take on food history involves dividing ancient people into "hunters" mythic fat-burning intermittent fasting meat-guzzlers who "didn't know what a carbohydrate was and they didn't need to." The modern remnants are the Maasai and Inuit. Then there were the "gatherers" who ate carbohydrates and protein in the form of fruits and vegetables, "this is the basis for today's vegan diet. It is practiced in multiple cultures around the globe, because if you grow your own food, that's what's available." Yes...the vegan tribes of India, oh wait, there is no such thing. And has Lustig ever raised his own food or visited a farm? Where do you think most farmers are getting fertilizer from? Hint: it's not vegan.
And the Maasai, while they may sometimes be fat burners, are not a low-carb culture. As for ancient foragers, there is a reason they have been called hunter-gatherers, not hunters AND gatherers. In fact the vast majority of foraging peoples in the Ethnographic Atlas eat fairly mixed diets, the people who are primarily hunters or gatherers are exceptions.
But Lustig has to make up this false narrative so he can get to his all-encompassing theory of all our problems (and also because for some weird reason he wants to pander to both the Atkins and plant-based folks, a weird thread in this book), which is the "Omnivore's Curse"- "it wasn't until we became gourmets, eating fat and carbohydrate in the same meal, that our cells first felt the wrath of mitochondrial wear and tear." Apparently, with the advent of farming we started mixing fat and carbohydrates together in meals and thus we became diseased, because in nature there are no foods that have both things, which means somehow that we should take our lessons and cease our evil cooking of potatoes in butter. "This accounts for the appearance of metabolic disease with the advent of trade in the early seventeenth century; before that, food was still a function of what you killed or you grew yourself. Eventually, we became gourmands, eating fat and carbohydrate in the same food."
Reminds me of my maxim not to take advice on food from people who don't actually seem to like it very much. My friends and I have a historical eating club and this Saturday is our dinner based on ancient Mesopotamia. I still have some mead (liquid carbohydrates mmm) left over from our Viking dinner, though we might have some ancient beer as well. For dinner I am making lard-rubbed goat leg with cumin, mastic, coriander, mint, and ginger. There will be sides of roasted barley and roots. Yes, I will be mixing carbohydrates, fat, and protein in one meal, which presumably people have been doing since they have been cooking. Pottery dates well into the Paleolithic, and before that people probably used other containers to mix things together. We know they were cooking because they left residues of grease and boiled fruits and all sorts of other things. Because humans are curious creatures and some of us really do like to play with our food (though as Gary Nabhan has pointed out, there may be some evolutionary reasons some cultures adopted things like spices).
Some people cook less than others- for example the Hadza don't seem to cook very many "recipes" though they do mix baobab (which contains both fat and carbohydrate) with honey for a drink sometimes. It's funny that Lustig later mentions that Ancel Keys in his heart disease study left out populations like those in Tokelau- in Tokelau their diet is starch and coconut. If mixing fat and carbohydrate were an issue, we would have been the way we are now for a very long time. Not that I think ancient people were perfectly healthy- for example, both Egyptian and Inuit mummies show atherosclerosis, though back then it may have been caused by constant infections and cooking smoke inhalation rather than food and there is no evidence it caused any mummy's death. Lustig does also make a good point that heart disease was a problem in the 1930s, back before the "obesity epidemic".
When I think of my very slim (though probably wearing a corset) great-great grandmother pictured here, I don't think of diets based on protein, fiber, and water. I think of people who ate reasonable natural homemade food. The same food I eat now. I doubt she would have touched things like the Slim is Simple Peanut Butter Pie (which contains ingredients I actually do try to avoid: low-fat dairy, industrial whey protein isolate, and extremely high omega-6 peanut butter, cooked almond flour...he recommends leaving the honey out of the crust, which is funny because it's probably one of the healthier ingredients) with a ten foot pole.
She didn't count calories, and neither have I. As someone who eats made-from-scratch foods that are highly variable it would be pretty pointless for me to count calories, as it would be inaccurate. I know when I'm losing weight I have a calorie deficit though, even if it is going to not be possible to quantify it accurately. Some people find success with trying to do the math, but I always found it easier to try things that have been shown in studies to subconsciously reduce the amount of calories eaten. One of these is to eat a lot of protein, which is funny because that's one of Bailor's main strategies. Though it certainly never made me stop thinking of other foods, and I had significant energy issues when I was on the very high-protein, low fat, high fiber kind of diet Bailor advocates. Frankly, I felt sick and catatonic, but I guess his diet works for some people, and not for others, the same way some weight loss diets work for some and not for others. Because nothing to do with the human body is simple. Slim is not simple.
I read an advanced copy of Why Women Need Fat when I was moving and because things were so hectic, I didn't have time to review it before it was released. I haven't heard that much about it though, except for this interesting interview with one of the authors in Salon. It's co-authored by Dr. William D. Lassek and anthropologist Steven Gaulin.
It's an interesting book, but it's slightly hampered by the fact that their theories and prescriptions are both quite complicated and controversial. Unlike most other diet books, the authors are not claiming that their diet will make you thin. In fact, they emphasize the importance of body fat to women and the unique factors that influence women's health risks.
So the book opens up a can of worms because it addresses fat in women, as well as evolutionary psychology. Talk about hot-button topics! But they are indeed strange bedfellows and it's interesting to see the synergy between them both.
The first chapter of the book addresses similar territory as Good Calories, Bad Calories with a history of how dietary fat, particularly saturated fat, became unfairly demonized by Ancel Keys and friends. But there is more discussion regarding the rise of polyunsaturated fats, which were erroneously believed to be a healthy alternative to the naughty animal fats.
Ironically, the next chapter starts with a discussion of Denmark, where women eat more saturated fat than Americans, yet they have lower rates of obesity and heart disease. It's ironic because last year Denmark stupidly started taxing saturated fat to discourage consumption. But here the book diverges a bit from Taubes because they note that actually sugar is a smaller share of calorie consumption in the US than it was in 1961 and overall we eat about the same amount of sugar as the Danes. They also note that the idea that carbohydrates are the culprit also doesn't make sense if you compare countries like Japan to the US.
Instead the authors look towards what they call the single biggest change in the American diet in the past forty years:the enormous increase in vegetable oils high in polyunsaturated fat, particularly the omega-6 variety. We consume more soybean oil than any other country in the world. That's been great for industrial monoculture farmers and food corporations, but hasn't seem to have done much good for our health. To add insult to injury, many of the oils introduced into the diet were not only mostly omega-6 fat, but also were partially hydrogenated, which created trans fats. Trans fats are pretty much unanimous considered extremely detrimental to health even in small amounts (as an aside, on the issue of women and fat, I think it's criminal that the Girl Scouts teach our young women to sell cookies that still contain trans-fats.)
Most food corporations have switched away from trans fats, but polyunsaturated oils are still considered healthy by many, including the USDA. Even people who aren't cooking with the oils are getting generous servings in nearly everything, from salad dressings to baked goods.
But here is where I get skeptical- the authors say that omega-6 could be a cause of weight increases in the population because it's converted into arachidonic acid. But if arachidonic acid is the issue, it makes the later dietary recommendations in the book seem suspicious, because most animal products are rich in arachidonic acid. And many of the studies they cite simply show that people who are overweight have higher blood levels of omega-6, but that doesn't tell us that the omega-6 was the cause. Considering that omega-6 fats are added to almost every processed food, you could blame it on an assortment of things from the palatability of the food (The End of Overeating) to wheat (Wheat Belly). However, it is interesting that it seems that some studies show that the weight gain from those eating diets very high in omega-6 is disproportionately distributed in the waist.
So how do they think this all works? They say that omega-6 makes us heavier by producing certain types of signaling molecules called eicosanoids, which promote the growth and development of fatty tissue and fat storage. Another factor is that such eicosanoids make white blood cells more active, which increases inflammation.
Much like Wheat Belly did with wheat, they also frame their villain as an addictive drug, since the body can make marijuana-like molecules out of arachidonic acid called endocannabinoids. Yes, cannabinoids, like marijuana, and the authors claim that it can stimulate the appetite similarly. But then it goes back to the fact that if this were true, wouldn't other foods rich in arachidonic acid cause similar problems? And those foods include things like meat and eggs.
I think they erroneously dismiss Kressler's book by focusing on sugar, when in reality Kressler also pegged processed fat as a villain as well, just one that works in synergy with other components of processed foods, which seems more likely to be the issue with these omega-6 rich vegetable oils than arachidonic acid.
Either way, through the studies that show omega-6 can cause weight gain disproportionately in the waist seem quite tentative, it is an interesting thing to think about, especially since several chapters focus on the importance of fat distribution.
These are the chapters bring in evolutionary psychology, which discuss controversial theories on the functional attractiveness of the waist-hip-ratio. Anthropologists have surveyed hundreds of cultures across the world and one of the few measures of attractiveness that seems fairly constant is that men seem to prefer a waist to hip ratio between .68 and .72 (even blind men). Does this actually mean anything evolutionarily? Is there an adaptive reason men find this attractive?
Human women are unusual in the first place by how fatty we are. A slim woman can have a body fat percentage of 30%. A chimpanzee female has a body fat percentage around 5%. In this metric, we are closer to whales or polar bears than other primates. The fat is usually concentrated in the buttocks, breasts, thighs, and hips. Studies have shown that the average man finds fat in these areas particularly attractive.
What is this fat for? Interestingly, women tend to lose the fat in these areas as they have children even if they gain weight overall and have plenty to eat. The lose correlates to the number of children a woman has. Lassek and Gaulin found that most of this fat seemed to be lost during nursing. During this period, an average woman eats less than she needs and instead seems to use up this lower body fat.
Why is this happening? It doesn't make sense that women would be just using this fat to give the baby extra calories, because otherwise they would eat more.
Turns out that there is something in this fat tissue that the developing infant brain really needs. The human infant brain is unusually large and it's not just hungry for calories, it's hungry for fat. In particular it's hungry for DHA, the immediately usable form of omega-3 fatty acids that has been found to be crucial for optimal infant brain development.
Unfortunately, the diets of most American women only provide half of the DHA that a pregnant woman and her infant need. Another type of omega-3 fatty acid, Alpha Linoleic Acid (ALA) can be converted to DHA, but this conversion varies (though interestingly pregnant women have upregulated conversion and the placenta also has the ability to push DHA "uphill" creating a higher level of DHA in the infant's blood than in the mother's) and can be down-regulated by excessive omega-6 in the diet.
The authors theorize that towards the end of the pregnancy, a woman eats less in order to foster utilization of her own fat tissues that are rich in DHA. The fat in the hips, buttocks, and thighs has more DHA than the fat in other parts of the body. This DHA has been accumulated over many years, starting in infancy.
I read a frightening Facebook conversation I witnessed in which a girl was bragging about how her thighs didn't touch, another girl mentioned that she was so mad that her thighs kept touching even though she had gotten "thin.". Like this question on Paleohacks, many women find that weight seems to come off everywhere but the thigh/buttock/hip region where the gluteofemoral fat lies. This can be frustrating in a culture where slimness everywhere but the breasts is desired. But seen in the light of the importance of this fat, it makes sense why the body resists mobilizing this fat when weight is lost and many women can't achieve the thinness they want in this region without getting so thin everywhere else that they are dangerously overweight or their ribs are showing. These women don't have "lipodystrophy," they are normal women whose bodies are trying to remain functional in a world where our body ideals have become dysfunctional.
The authors own research that suggests that women with more of this important fat have smarter children.
They also attempt to find a reason why men seem to like small waists, despite the fact that they are associated with low BMI, which is associated with poor fertility. Women aren't just fatter than other apes, we have the riskiest childbirth, a consequences of our infant's oversize brains. The first birth is always the most risky because the birth canal is un-stretched. The authors present data that shows that smaller-waisted women have smaller babies (even though they eat more during pregnancy) and thus easier first-time childbirth. So for most of evolutionary history, it would seem more beneficial for a woman to be neither too heavy, nor too thin, with the fat concentrated in the buttocks, hips, and thighs.
But once the first baby expands the birth canal, a woman can afford to have a bigger baby. And biologically, bigger babies might not be good for a first-time mother, but if they make it out of the birth canal they are more likely to survive and thrive. So the authors theorize that the reason many women find that they are starting to get bigger around the waist after they have their first child is that the extra weight will benefit the next child.
The mechanism they use to explain this is leptin, which plays many important roles in fertility. It also tells a woman's hypothalamus how much body fat she has and then uses this as a guide to tell the body how much of the nutrients that come from meals that she should store and how much should circulate in the blood. When a woman has higher body fat, her hypothalamus "tells her cells to pay less attention to her insulin's request to save." Higher fat stores mean more fat, sugar, and amino acids in the blood. Nutrients are more available to the placenta in the first place and the brain is more amenable to requests for more. But too much fat can be a bad thing at a certain point. Heavier mothers are more likely to suffer from preeclampsia, which could be because the placental hormones that "request" more nutrients are overactive and then the cells of the placenta burrow deeper into the wall of the womb to access the biggest arteries, causing an immune-system reaction. Interestingly, it's more likely if it's the first time a mother is carrying a particular man's child and becomes less likely as she bears more children by the same man.
So Lassek and Gaulin theorize that a larger waist signals to a man that a woman might already have a child to take care of and has also already used up some of her valuable DHA-rich fat. Another controversial idea they introduce is that even a child-less woman will gain weight as she ages because she is likely to have fewer children, so in order to increase the likelihood of genes being passed on, it's more important for any children she has to survive because she might not get another chance. So her waist accumulates fat in order to have a bigger baby, even if that means increasing the risk of the childbirth.
But even if some weight-gain is desirable, things seem to have gone haywire recently. Women gain this weight much earlier and are overall much heavier than their foremothers. They also suggest it's possible that the low amount of DHA in our diets might be responsible for higher overall fat accumulation, reasoning that if a woman gets half as much DHA from her diet as another woman, she will have half as much DHA in each pound of fat. So in order for her body to accumulate an optimum total amount of DHA, she will need to store more fat. I didn't feel the evidence was very strong for this theory, mostly the observation that women are thinner in countries with high-DHA diets, but it is very interesting.
The next part of the book is devoted to the idea of achieving "a natural healthy weight." It examines several studies that show that being slightly overweight (BMI of 25-29) seems to actually be healthy for women (but not for men). A lot of this stuff is similar to what was in the Healthy At Every Size book I read.
Another reason why older women might tend to be overweight, was that in the past this represented a protection against infections like tuberculosis, which killed many thin women. This may be because fat confers more active white blood cells. Luckily, estrogen protects women from some of the downsides of having more fat. Higher estrogen means higher HDL, which is good cholesterol. In general, women are seven times less likely than men to die of coronary disease before age sixty-five (I suspect personally that iron levels play a role here too). There is a downside, in that higher levels of estrogen seem to be related to higher risk of breast cancer, but that seems to mainly hold true for obese, not overweight, women. Overweight women are also more likely to develop type 2 diabetes. The authors recommend that women can follow a high omega-3, low omega-6 diet to help mitigate this risk regardless of a woman's weight.
Some other interesting facts are mentioned, such as the fact that heavier women are less likely to break their hips. Hip breakage is a common cause of death in the elderly. However, heavier women are more likely to have arthritis.
But overall, they say that the focus on heaviness itself is probably misguided, because it's where the fat is distributed that matters. Large waist size in particular seems to be associated with health risks. Interestingly, in the 1990s, about half of women in the overweight group had waist sizes in the unhealthy over-35-inch range. Today roughly three out of four do and 1/7 "normal" weight women also have this problem.
Unfortunately, dieting just doesn't work for most people and in fact people are often worse off after they try diets. Lassek and Gaulin say that calorie restriction makes women miserable and often ends up raising their set points. Instead, they say women should try to return to more human-appropriate diet, with special attention to consuming more omega-3 and less omega-6.
They have a section on reducing omega-6, which mainly focus on fried and processed foods that contain soybean or corn oil. They also recommend being careful about poultry, though weirdly they don't mention pork. They also have a whole section on potatoes as hidden sources of omega-6, but all the potato-foods with high-omega-6 levels are fried or cooked with high omega-6 oils, so it's not actually the potatoes that are the problem.
In order to boost omega-3, they recommend grass-fed meat, wild fish, and/or fish oil/algal DHA supplements. Annoyingly, they don't mention some potential caveats to supplementing such as "fishy burps" and general gastrointestinal upset. It's also definitely not a paleo diet, because they recommend you eat wheat, since it doesn't have much omega-6. They also recommend canola oil, which I personally view with skepticism, particularly if the goal is to return to the diet and thus the weights of our foremothers. I wasn't such a fan of this section of the book. It's clear the authors know much about anthropology and medicine, but not that much about food. I'm glad they are promoting grass-fed meat, but it honestly doesn't have that much DHA. You would have to eat 4.6 lbs of grass-fed beef to get the recommended 1.6 grams of DHA.
And then the rest of the book is about finding your realistic "natural weight," which is the weight your body will gradually shift to once you adjust your diet. This takes into account age and bone structure. Unfortunately, it also involves four steps of calculation. And there are also some eating tips, which are kind of easier said than done:
The interesting thing is that nuts have tons of omega-6. Shouldn't they be bad then? In the end I applaudan approach that recognizes that body fat plays a unique role in women and discourages the eating-disorder-like behavior and unrealism of traditional dieting. Unfortunately, while I think most bloggers I read have a healthy attitude, I see ridiculous bro-science about women's weight like this post on "Top 10 ways to get Skinny Fat." Besides the obvious fact that there are plenty of women who do those things who have ideal or very low body fat, I thought the choice of "scare" picture was telling:
Seriously? That is not a picture of an unhealthy "skinny fat" woman. In fact, there are plenty of women who eat the "magic" paleo diet that many of these sites tout and have much more body fat than that. Not that I think that's a bad thing. Those women are probably much healthier than some of the health bloggers I've seen who are so thin that it really worries me.
That's one limitation to the book. Despite having a more realistic attitude about weight than most books, it still seems to be primarily targeted towards people who want to lose. But the theory the book contains implies that not having DHA-rich fat stores would be bad as well. I personally believe it's possible even for women who are skinny to rebuild healthy curves. I was very very thin when I was raw vegan and over the years of eating fertility-supporting foods like butter and fish roe and improving my digestion I have laid down more fat tissue (and quite a bit of muscle) on my chest, thighs, and buttocks without increasing my waist size very much. I've received similar comments from other women. Is it any surprise that Marilyn Monroe ate a similar diet?
Also, let's get real here. Just like it's absolutely hilarious that writers can quote studies that show foragers are healthy in one breath, and demonize foods that make up most of their diet in another, I think it's weird to tout a very modernized female ideal as part of a "paleo" approach considering that forager women simply don't look like that and that art from the actual Paleolithic seems to portray a culture in which fertility-related fat was venerated.
I also enjoyed the evolutionary theory for the role of body fat in women. But I think their practical advice seems awkward and limited by lack of food expertise. I also think the evidence that omega-6 is responsible for obesity is somewhat limited, as laid out by a recent post by Stephen Guyenet, though I definitely agree that it can cause other problems. And maybe the association only holds up for women?
Hands down the best health book I read this year was The Definitive H.P. Lovecraft: 67 Tales of Horror in One Volume. Despite being about fictional creatures of terror from unholy abysses, I learned quite a bit from Lovecraft's depiction of the universe. The humans in Lovecraft's stories are baptized into the knowledge that the universe is older and more incomprehensible than they could have ever imagined. While the monstrosities and sublime ancient temples are quite terrifying, what is even more terrifying to the humans in the stories is their realization of how little they can ever really know. Those that get a taste of the mysteries often only do so at a very high price.
They called up some image from deep cells and tissues whose retentive functions are wholly primal and awesomely ancestral
I'm not sure I have any sort of particular cause in terms of diet anymore. It's gotten to the point where I'm just interested in the Paleolithic and not really very concerned with arguing about whether or not a potato is safe to eat or not.
Wouldn't it be nice if our nice little narratives worked out? The ones in which Homo sapiens sapiens is the protagonist and you can trace his illustrious evolution neatly through the ages. And he fits rather nicely in your romantic stories about hunters and mammoths so you can tell people that this is their heritage.
But in reality you don't get your nice story. Instead, you get ages and ages of dust and bones, in which every little shred of a skeleton is a prized, but dim, glimpse into ages long past.
In my anthropology class last year, one of the skull casts that caught my attention was the Kabwe skull, which is estimated to be between 125,000 and 300,000 years old. Not quite Homo Sapiens, the skull has some features of modern humans and some of Neanderthals. Homo rhodesiensis? Homo heidelbergensis? Homo sapiens rhodesiensis? Anthropologists could argue about it all day. Either way, this person died a miserable death. The first known incidence of dental infection in a hominid as far as I know, and the infection was bad enough to put some ugly holes in the bone and eventually kill the individual.
There is only so much you can tell from bones, which leaves lots of room for people to make stuff up. Stable isotope analysis seems quite promising, as they can potentially tell you the source of protein in the diet, but they can only tell that and nothing else, and the isotopes are subject to interpretation. For example, Lierre Keith in her error-ridden Vegetarian Myth claims that stable isotope analysis showed Australopithecus africanus ate meat, but in reality the data only said that the protein was from carbon-13 enriched foods, which could include grasses and sedges as well. Later investigations revealed that the carbon-13 probably was more likely from grasses and sedges, but the data is up for interpretation. Before you tear up your lawn to make dinner, it might be worth remembering that Australopithecus africanus is only thought to be a possible human ancestor and was quite a bit different from a modern human.
That said, stable isotope analysis puts to bed the idea that early Homo sapiens were getting their protein from the Paleolithic equivalent of tofu or the idea that Neanderthals definitely only ate meat (turns out that some ate fish too...maybe).
"Maybe", "later investigations revealed", "thought to be"- these are things that should give you pause whenever you encounter stable isotopes being used to argue about ancient diets. Have I confused you? Good, now you are less vulnerable to the abuse of bones in the name of various causes one way or another.
It can be used to estimate the trophic level and origin of the protein, but it cannot tell you whether the person ate a teeny tiny auroch steak and then 17 potatoes or whether they only ate mammoth. It cannot tell you the percentage of protein in the diet. It cannot tell you how much protein in grams. That information was lost when the person died.
Then there is the use (and mainly misuse) of animal bones and modern data from wild game species to argue various things about ancient diets. I read this latest paper, Man The Fat Hunter, with absolute glee because it uses many of the same questionable methods and comes to an opposite conclusion of many past papers, which overemphasize protein. The questionable method is taking bones of animals possibly consumed by ancient humans and plugging them into an equation with the modern wild game data and then saying this or that about the amount of fat or protein in an ancient diet. In this paper we have elephants featured, which is great, since elephants are very fatty, but unfortunately their presence or absence in bone assemblages is not a food diary. There is no way to know how often elephants were eaten, so there is no way to make an even sort-of accurate conclusion about %elephant and therefore %elephant fat in the diet. Whether or not the hominids in question were able to cook is also a point of contention.
One good thing about the paper is that it does try to address one issue, which is ceilings. In this case, the paper mentions possible ceilings for protein consumption and fiber consumption that could be used to build diet-estimating equations. Unfortunately, there are quite hard to determine, as they are affected by human genetic variation, culture, and environment. For example, there is possible a ceiling on the consumption of raw plant materials based on gut morphology (though if you have only skeletons you can only speculate on this) and toxins, but that ceiling can be raised with access to cooking and processing. To complicate matters further, their food sources may have been things you haven't even thought about eating. You can try to figure it out based on local paleobotany and starch microfossils, which can be hard to read. Once you've established that a microfossil on an ancient tooth is possibly Bromus secalinu, you might be able to figure out a little about how it was processed based on microfossil shape and local conditions and if you have a rich lab you might be able to collect it and do a full nutritional analysis, but you still have no idea how much of the diet it made up.
And what is the protein ceiling? It depends on the rest of the diet, an individual's health, and possibly genetics. Modern genetics adds some depths to the picture. For example, the fact that genetic adaptations for a starch-based diet seem to be part of fairly recent selective sweeps may give us a clue that Paleolithic human ancestors probably weren't eating mainly starch, but statistical genetics is in its infancy.
But genetic variation can add more confusion if we are talking about what to eat now. Many "paleo" dieters have learned the hard way that they carry alleles for hemochromatosis, which means they can over-accumulate iron, which has some pretty nasty effects. It would be interesting to know where this came from, as it clearly would be a liability if an ancient human ate meat-based diet, but ultimately whether or not Paleolithic hominids carried such alleles in high frequency is irrelevant to the millions of men (and some women) who are at risk. This represents a ceiling for them, though it can be modified through modern medical treatment.
Normal is of limited use if you are on the end of the bell curve- this is where personalized medicine and self-experimentation is important
So while it's not completely true we have no idea what Paleolithic hominids ate. We do have some good clues, but reconstructing the diet is pretty hard. That doesn't stop people from trying, but their results are on some pretty shaky ground.
My own method, which is about as accurate as some of these equations, is to observe the fact that a medallion of relatively lean wild boar goes absolutely perfectly with a seared hazelnut crust and dollop of mashed celeriac or potatoes cooked in broth. Maybe there is a reason that dishes containing a protein on a bed of delicious carbs AND fat (but not overpowered by them) is so appealing to so many? Who knows.
One thing I will miss in NYC are the fantastic restaurants. I particularly applaud the trend of restaurants that go whole hog and use real bone stocks and animal fat in their dishes. Obviously, these restaurants are pretty vegetarian-unfriendly and have been a little controversial.
Unvegetarian, unapologetic animal eater restaurants
The Momofuku restaurants were instrumental in jumpstarting the pork belly and rich broth trends. There are several restaurants in the group (and one in Sydney and Toronto now). There are plenty of vegetables on the menu, but often they are drenched in delicious pork fat. One of the best dishes is chanterelles with bone marrow, a luxurious and fatty combination, but only available seasonally. The various traditional Southern Hams make an excellent appetizing and the offal dishes are not to be missed.
I think Salt & Fat, which is in my neighborhood in Queens, is a little inspired by Momofuku and also be Williamsburg's excellent Traif. Their appetizer is bacon-fat popcorn, which is amazing. I recommend the yellowtail tartare, the delicious ribs with homemade BBQ sauce, the incredibly rich salads with all kinds of animal fat bits, and the hearty oxtail terrine.
I'm mentioned Takashi like a zillion times, but that's because it's a temple of delicious meat and they do offal so well that it's the perfect place to try crazy things. I LOVE the sweet breads. They seem kind of scary at first, but they melt in your mouth. The liver is also not to be missed. I don't usually like liver that much, but their liver is marinated so perfectly that it's delicious raw. I've never had anything I disliked on the menu and I think I've eaten almost everything on it.
I really like Fatty Cue because they use lots of delicious animal fats with dashes of fish sauce for flavor. The dishes are salty, fatty, tangy, and spicy. I particularly recommend the coriander bacon.
Because it's Brooklyn, they actually probably have some real vegetarian dishes at Palo Santo, but the chef here cooks everything else with real house-made animal fats and stocks. The cuisine spans many countries in Latin America and uses ingredients from many local farms.
Vegetarian Restaurants I actually eat at:
Saravanaa Bhavan is one of my favorite places for Indian food. I love idlis, which are steamed fermented rice/lentil cakes served with a spicy soup called sambar.
Rockin Raw makes an excellent raw-vegan cinnamon roll that's gluten, soy, and nut-free. When I crave a sweet treat, I go here.
Occasionally I get a weird craving for falafel. Organic Avenue's raw falafel is oil-free and gluten-free. To me, it tastes as good as the real thing.
Bacon Branzino @ Salt & Fat
This is one of the better articles I've read lately. It addresses serious errors common to works that cite the Paleolithic and foraging societies at being an apex of human welfare. Some of these errors include
For example Lee wrote that the San "worked" only 20 hours a week. Unfortunately, his definition of work was a little questionable. Turns out they work as much as I do:
investigation revealed that what he defined as subsistence activities occupied adult !Kung for about 2.4 days per week on the average, or for about 20 hours. This rather leisurely work schedule, it is claimed, managed to yield an abundant and nutritionally well-balanced diet. These findings were somewhat puzzling to some anthropologists who have conducted similar investigations in similar societies. Hawkes and O'Connell (1981) observed that the Bushmen figures were one-half to one-fifth of the time required by the Alyawarra, a central Australian foraging group. They expressed some surprise because the !Kung and Alyawarra are very similar in habitat as well as technology. The difference, it turned out, was explainable by Hawkes and O'Connell's definition of work: in their calculations of work, they included time spent in processing food as well as hunting and gathering it...."In addition there are the important tasks of manufacturing and maintaining their tool kit and, of course, housework-for the !Kung this involves food preparation, butchery, drawing water and gathering firewood, washing utensils, and cleaning the living space. These tasks take many hours a week" (Lee 1984:51-52).6 When these tasks are added to "subsistence work," the estimate per week is 44.5 hours for men and 40.1 hours for women. Lee is quick to add that these figures are well below the 40 or so hours per week that people in our own society spend above their wage-paid job doing housework, shopping, and other household chores. What seems to be at issue here is what we mean by terms such as "work" and "leisure" in the context of hunting-gathering societies---or, indeed, in the context of any society.
What about all that time spent lounging about?
And then there are the G/wi Bushmen, who reside in the central Kalahari. According to Silberbauer (1981:274- 78), they spend a good part of the day (from about 10 A.M. to about 4 P.M.) resting in the shade, not because they have "chosen" leisure over work or have limited wants, but because to venture out in the blistering sun for any time would expose them to dehydration and heatstroke. Throughout much of the year, there is little cloud cover to provide some relief from the withering heat; unshaded temperatures can reach 60'C (140'F), and sand temperatures as high as 720C (161 F) have been recorded. During the early summer months, all the G/wi lose weight and complain of persistent hunger and thirst (Silberbauer 1981:274). Hardly a "picnic outing on the Thames."
Also sheds further doubt on how well humans are actually adapated to the savanna.
What about using the !Kung diet to make inferences about what a healthy Paleolithic diet was?
Truswell and Hansen (1976:189-90) cite a string of biomedical researchers who have raised doubts about the nutritional adequacy of the !Kung diet, one going so far as to characterize one Bushmen group as being a "clear case of semi- starvation." Truswell and Hansen (1976:190-91) themselves have concluded that the data suggest "chronic or seasonal calorie insufficiency may be a major reason why San do not reach the same adult stature as most other people."... although he softened his opposition somewhat by conceding that the smallness of the !Kung might have something to do with undernutrition during childhood and adolescence, and he went on to note that !Kung raised on cattle posts on a Bantu diet of milk and grain grow significantly taller (Lee 1979:291).
This paper also mentions the fact that the vast majority of the !Kung consider mongongo nuts an undesirable fallback food. People who want to exploit the !Kung to talk about the Paleolithic tend to believe that they have been foraging since the Paleolithic and the nearly agropastoral people have had little effect on their lifestyle. I will address more of this myth in later posts, but needless to say, the evidence points to the fact that the !Kung have had trading relationships with agropastoralists and their current state is much more precarious nutritionally than it was in the past.
What is mainly missing from their foraging diet these days is fat:
We hear so much these days about the overconsumption of fat in the modern industrial diet that we sometimes forget how important some level of fat consumption is to normal human growth and the maintenance of healthy bodily functions. Animal fat, says Reader (1998:124) is "the proper measure of affluence.".... Hayden's (1981:421) observation is especially relevant here: "I was astounded the first time I saw Western Desert Aborigines ... kill a kangaroo, examine the intestines for fat, and abandon the carcass where it lay because it was too lean. Upon making a kill, Aborigine hunters always open the intestinal cavity and check the fat content. Virtually every ethnographer with whom I have discussed this observation confirms it, yet such details are seldom reported in the literature."
But at least they all love to share with each other...right?
Here, we were told, in the more marginal areas of the world were societies that were depicted as just the opposite of the industrial West, societies characterized by egalitarianism, widespread sharing of resources, an indifference to material possessions, societies whose members seemed to live in harmony with nature and one another and whose wants were modest and easily satisfied....sharing that goes on seems to be as much motivated by jealousy and envy as it is by any value of generosity or a "liberal custom of sharing." In his survey of foraging societies, Kelly (1995:164-65) notes that "Sharing... strains relations between people. Consequently, many foragers try to find ways to avoid its demands .... Students new to anthropology..,. are often disappointed to learn that these acts of sharing come no more naturally to hunter- gatherers than to members of industrial societies."...(1982:55) recounts the incident of an elder Bushman who asked him for a blanket. When Lee responded that he would just give it away, the elderly Bushman replied, "All my life I've been giving, giving; today I am old and want something for myself." Lee adds that the sentiments expressed by this elder were not unique. Perhaps "human nature" is not as different from society to society as we have been led to believe.
Perhaps there was a golden age, where fatty game was more abundant and sharing came easily. But the Bushman don't tell us much about that and overall it remainds a speculation.
Yesterday I read an interesting paper in Human Brain Evolution: The Influence of Freshwater and Marine Food Resources. I have some issues with this book, which is a collection of papers, but there is some great information. One of the interesting chapters is Lessons from Shore-Based Hunter-Gatherer Diets in East Africa. Some of it is available as this paper Milk in the island of Chole [Tanzania] is high in lauric, myristic, arachidonic and docosahexaenoic acids, and low in linoleic acid reconstructed diet of infants born to our ancestors living in tropical coastal regions.
Chole is an island in Tanzania, home to a population that is a mixture of various peoples from the African inlands, the legacy of the Arab slave trade. The paper describes their diet as being coconut, marine fish (which they boil), vegetables, fruits (oranges, mango, and banana), and an occasional flying fox. I do not believe this description is completely accurate. The researchers were looking for a culture that eats close to the "paleolithic diet" as described by Cordain: lean meat, fruits, and vegetables. Unfortunately, this culture does not exist, which leads to the bizarre paradox of using cultures that eat either high-carb, high-fat, or both to bolster the idea that this diet is the best for humans. Later in the paper they use this hypothesis and the data from the people of Chole, to estimate a paleo diet that is nothing like the diet of the people of Chole. They published a separate paper on this, which Don at Primal Wisdom has blogged about. I am more skeptical than Don, as I don't believe the diet we evolved on would be close to the upper limit of the % calories of protein that is the estimate for the max capacity of the liver to convert excess nitrogen to urea (35%)*. Their estimated ratios are suspiciously close to the zone diet...
I'm not a fan of the method of deciding what is healthy and then trying to fit the ancestral evidence into it, which seems to be their main method. They repeatedly say that staple carbohydrates weren't part of Paleolithic diets, only citing Cordain, who has no evidence for this. I notice they don't hawk low-fat much explicitly, despite their estimated paleolithic diets, since they are working with data from people eating high-fat. But I digress, because I really just wanted to talk about breast milk here and their breast milk data is great. They have data from the people of Chole, three groups of fish-eating controls (Kerewe, Nyakius, and Nyiramba), four groups from the inland (Hadza- who are foragers, Maasai, Songo, and Iraqiw), plus they presented historical data from Dar Es Salaam and several Western countries.
Here we can see the people from Chole very high amounts of two particular saturated fatty acids: lauric and myristic. The Kerewe have similar levels of myristic and the people of Dar es Salaam have similar levels of lauric. Chole and Dar es Salaam are located in a costal region where palm and coconut trees are abundant. Other places where coconut is eaten frequently like Dominica and Surinam, also had high levels of lauric acid. What about myristic? The authors explain that the Kerewe do not consume coconut, but have a high carbohydrate intake from ugali (a corn/wheat porridge) and muhoho (cassava). They do not explain why other cultures eating a high-carbohydrate diet don't have similar levels or why the levels in the Chole are so high.
Despite it not being mentioned in the paper, the Chole do eat plenty of carbohydrates (though in what amounts remains to be studied). This book mentions that they grow potatoes, corn, millet, squash, cassava, and rice. This ethnography on storytelling also mentions these crops. Here is a woman in New Scientist, pounding rice:
Did their culture change all the sudden? Why aren't the authors mentioning these foods? Out of the blue they say that "carbohydrates cause the highest increase in total cholesterol/HDL cholesterol (Mensink et al., 2003), suggesting an atherosclerosis-promoting effect of the carbohydrate-rich diet of Kerewe." I can't find any evidence that the Kerewe suffer from this condition and considering how similar their diet is to the Kitavans, I suspect that they don't have it.
Apparently you can get lauric and myristic acid from coconut, but there is evidence that carbohydrate-rich diets raise the milk content of medium chain fatty acids as well by de novo synthesis from glucose. I will have to look at the papers cited, but perhaps this mechanism is suppressed somehow in people with excessive linoleic acid in their diets, which would explain why the people of Palestine have low levels, for example. The authors not that in their data set, lauric acid correlates inversely with linoleic acid and positively with DHA and AA.
As for why this carb to medium chain fatty acid mechanism exists, we get no speculation, but another citation to Cordain for the idea that carbohydrate-rich diets were not part of our dietary habits.
No matter how they got there, medium chain fatty acids in breastmilk seem to be beneficial. They are easily absorbable as energy (especially since babies are in ketosis no matter what their mother's diet is), and they have antiviral and antimicrobial properties.
When were coconuts introduced into the human diet? The fact that much of the Paleolithic coastline is underwater and decomposition tends to be rapid in hot humid climates means the fossil evidence is scant. But a silicified coconut fruit was found in the Chinchilla sands in Southern Queensland from 2 million years ago, which suggests that they were widely dispersed even then, since the current origin of the coconut based on genetic studies seems to be East Africa (where humans may have evolved into our modern form) or the American West coast.
The breastmilk of Chole is very low in linoleic acid and pretty high in DHA, though not as high as in the Kerewe. This is not surprising considered their diet, which is rich in seafood.
How much exogenous DHA is needed for infants for optimum brain and eye development is currently under debate. The authors of this book believe that the DHA needs in infants require the mother to consume seafood, or at least large amounts of DHA-rich organs like brain (though insects also are a source of DHA too). I'm not sure this is true myself, but would be curious to see the Hadza (inland foragers) compared to the people of Chole.
Hilariously, the breast milk of Chole VIOLATES formula recommendations of the Commission Directive of 1991 (I hope the recent ones have been revised), which recommend that lauric and myristic fatty acids be no more than 15%. 90% of Chole samples violate this recommendation. They also are too high in Arachidonic acid, which has a bad rap, but it is important for infant brain development and there is evidence its negative effects only occur when omega-3 is low. There is also evidence that infants cannot create enough of the needed AA from precursors.
The unfortunate fact is that often guidelines for synthetic substitutes like formulas are based on "normal" women. And considering the health of the normal people in the US, normal might be a bad thing. This paper points out that current data is taken from populations with high levels of degenerative diseases of civilization. According to nutritionism-ists like Marion Nestle, you need a bunch of studies to show DHA is needed in formula. Studies aren't the be-all and end-all, particularly if they are based on populations that are not living optimally. If I were forced to use formula, I'd rather have it be based on the breastmilk of a healthy population than wait decades for a bunch of studies and continue basing it on a bad dataset.
While I disagree with some assertions in this paper, as they seem to be bent by preconceived notions about macronutrients and the Paleolithic, it is very interesting and points to the need for more studies on populations like that on Chole before vegetable oil is introduced.
*I am working on a different post on this issue.
While I was doing research on variations in gastric acidity, I came across an interesting paper: Diet, reflux and the development of squamous cell carcinoma of the esophagus in Africa. It's interesting that a lot of conventional dietary advice on digestion is based on studies done in Africa that found that African agrarian cultures eating low-fat high-fiber diets had low rates of common Western digestive issues like hemorrhoids and colon cancer. Unfortunately they forgot to mention that there are a host of similarly bad digestive issues that are MORE common in such cultures, such as sigmoid volvulus and squamous cell carcinoma (SCC) of the esophagus. The latter they have tried to blame on everything from pickled vegetables to malnutrition to alcohol, with none of those hypotheses holding up very well.
A promising villain is linoleic acid, AKA omega-6 fatty acids, well known for their harmful effects in the ancestral health/paleo/primal communities. The epidemic of SCC tracks the widespread adoption of linoleic acid-rich corn as a staple, not just in Africa, but in regions of Europe as well.
I bet you are wondering why Americans don't have SCC. I think there are two factors, one is that higher levels of fat in the diet are protective, but I think another is that it's possible that a precursor to it is heartburn, which is widely treated in the US with proton-pump inhibitors. Those have some seriously bad effects, but they might prevent some types of cancer. I think it's better to remove the cause, but if you are going to continue to eat garbage, a PPI might save your life.
Linoleic acid may be causing heartburn by increasing levels of prostaglandin E2 (PGE2). In animal models, high levels of linoleic acid, particularly in combination with low levels of other fatty acids, lead to elevated PGE2. Other micronutrient deficiencies, such as riboflavin deficiency, might make it worse. PGE2 then inhibits gastric acid production and reduces the tone of reduces of the pyloric and lower esophageal sphincters, causing heartburn. If you thought heartburn was a Western disease, consider that 60% of people in Transkei, South Africa suffer from it. Untreated heartburn exposes the esophagus to damage from the acid, in the long-term this can lead to the development of abnormal cancerous cells. Trypsin can possibly squelch the growth of such cells, but the paper notes that the South African diet is also rich in vegetables that are trypsin inhibitors, such as beans and pumpkin. They also eat the very very bad for you vegetable known as Black Nightshade, which is a pepsin inhibitor. And a lot of people smoke. A bad combination leading to a cancer epidemic.
Since I have gotten rid of my GERD, I've wondered and wondered how I did it. I started eating a high-fat nutrient-dense diet, which was low in grains and free of vegetable oils, but not completely gluten or grain free. So that ruled out a gluten allergy as a major culprit. Wheat tracks as a cause of SCC too, but rather than an allergy as work, it seems like a complex inflammatory process is at play. We need to look at omega-6 as one of the true causes of GERD. It's also a possible connection between omega-6 and skin issues via the gut-brain-skin axis.
Last year I met a girl who was trying the paleo diet and complaining she "felt weird" and her stomach hurt. I asked her what she was eating and it turns out she was eating 5 tablespoons of coconut oil for breakfast! I told her that wasn't food, that it was an ingredient you can use to make foods or a supplement and that maybe she should try eating food. Later she said she felt better.
I guess there is some impression among certain people that because I and others don't think fat is *bad* that you should drown yourself in it. As far as I'm concerned it's a far cry from a certain Paleo cookbook that advocates trimming fat off of GRASS FED meat, throwing away the fat that is leftover from cooking grass-fed meat, and avoiding grass-fed "fatty cuts" like shanks to eating a pound of bacon for breakfast with a side of heavy-cream flavored coconut milk. Let's be honest: I don't eat that way. I cook with tallow that I save from the whole goats and lambs I buy, I certainly don't ever throw away any "fatty" cut, and sometimes I use some ghee, bacon, butter, or coconut milk as ingredients. I go through a pound of bacon a month, mostly because of my boyfriend, and maybe a can of coconut milk every two weeks and a pack of Pasture Butter a month. I never make any "paleo" desserts anymore and I don't eat very much dairy unless it's well-fermented and raw. Heavy cream makes my digestive system into sludge. I do eat some grains: I find my stomach is happiest when I include some rice in my diet every few days or so.
I suspect someone who is more athletic or who doesn't have IBS might tolerate more fat. But this is my personal "sweet spot." I do have experience doing almost-vegan paleo: starches, veggies, fruits, no added fats, and only shellfish as protein. Perhaps it could be perfected, but I found that my keratosis really was itchy and red. I also felt more depressed and had bloating. If I tried it again I would probably use some coconut milk with carrot juice or something in an attempt to get vitamin A, but maybe my body isn't suited for it because of my genetics and health problems. Maybe it's also different for people in different life-stages. I'm a woman of reproductive age, so it's possible my need for certain vitamins is higher.
I also would note that food sensitivities don't care about the paleolithic. It's very possible to be allergic or sensitive to a host of "paleo" foods from types of meat, to nuts, to eggs, to shellfish. I am personally quite sensitive to vegetables like broccoli, onions, and cauliflower. Honestly, they do a number on my stomach worse than any grain. I think people get caught up in the "paleo" paradigm thinking that because we evolved with foods like it, it must be good. But modern food sensitivities don't discriminate. I find that interestingly my stomach feels much better if I get starch from regular potatoes rather than sweet potatoes. The latter is considered "more paleo" though that stems from botanical ignorance.
Either way, I don't really follow an orthodox "paleo" diet either, though I do use what I learn about the paleolithic to think about what I eat. I think there is tons of room for experimentation, particularly as the evidence for starch consumption in the paleolithic becomes stronger and stronger.
I don't think there is much room for combining "paleo" with various religious philosophies and I'm a little dismayed that Chinese medicine has somehow crept in and become tolerated. I think if I blogged about how I use Christianity to tell me what to eat I'd get about a million angry comments. Remember, the mechanisms behind Chinese medicine are scientifically implausible and even if a few tiny studies show that Chinese medicine works, it's not because of supernatural forces like conveniently undetectable "energy fields" operating outside of the forces of biology, chemistry, and physics. I know plenty of people who follow a "paleo" diet that is compatible with their religion, such as kosher or halal folks, but they don't claim that their diet is somehow better because of it or that it explains their diet's success.
There has got to be a scientific explanation or I'm just not buying it...
It seems that some people were upset with the idea that I was attacking alternative medicine in the last post. No, I was attacking scientifically implausible theories of food being integrated by the ancestral food community. It's because people don't want to believe there are both unverifiable supernatural beliefs AND beliefs worth investigating to find out whether or not they have some natural basis or benefit.
Acupuncture, for example, is a system worth investigating because of the possibility that the ancient literature refers to real physiological processes, as Chris Kessler points out, and not energy fields (scientists have looked for these energy fields and NOT found them).
The idea that some Chinese roommates once told me that going to bed with my hair wet would cause demonic possession leading to pneumonia made me wonder if perhaps people in rural China did get sick from chills, but otherwise it is a supernatural belief.
Likewise, I am a huge fan of traditional Chinese foods, but when my waitress at my favorite restaurant in Flushing tells me I eat too much fatty "Yang" food and will get acne and clog my blood (that would be awesome since I have a mild form of hemophilia) I think it's worth investigating, but most of the time Chinese traditional food beliefs have been investigated, they have found to be incorrect or vast simplifications. I'm impressed at the latter, but I won't be basing my food choices on whether or not foods are "Yin" or "Yang." I suspect these beliefs have very little to do with Taoism anyway, as they were probably added on as Taoism blended with local folk religions.
Some of these folk beliefs lead to some absurdly unhealthy behaviors. I know Thai people who believe it's good to wash down beef, which is a "hot" food, with Coke, which is a "cold" food. And Chinese people who follow their fried chicken with heavily sugared red date tea because it's "Yin" and replenishes their "Qi." Since these beliefs are not based on real concepts, they are particularly vulnerable to industrialization.
Religions/folk beliefs and food: worth investigating and important tools for believers, but not always scientific.
A commenter on the previous post on the Mbuti pointed out that the mango they eat is not rich is fat, but in fiber. When I looked at the data it became clear that the data from the original paper reffered to the whole fruit including the seed I think. The fruit in question is Irvingia gabonensis. Further research turned up this very interesting book on how this is used:
The book also contains information on other easily refined fats like Borneo Tallow. I suppose the myth that early humans couldn't have had access to oils is busted...but remember that couldn't doesn't mean they actually did.
I would love to try any of these "jungle butters." I recently tried a South American fatty jungle seed marketed under the name SaviSeed (Plukenetia volubilis). While I am skeptical of their claim that they have more omega-3 than salmon, since the omega-3 in the seeds is ALA, which is less usable than the DHA in salmon, they were quite tasty and an interesting candidate for agroforestry.
The dika nut unfortunately is not yet considered commercially viable, but breeders are working on varieties that could be grown faster and have easier to crack nuts.
Edit: Oh, actually I have had Dika; at Buka in Brooklyn in Ognono soup! I remember it being very good!
Physical Anthropologist John D. Speth wrote a fantastic book called The Paleoanthropology and Archaeology of Big-Game Hunting: Protein, Fat, or Politics? It's kind of a crime that it's not more widely available. It sells for $134 on Amazon, which is totally lame. If you are a student though you can probably get it for free. For my institution Springerlink had a free ebook download! I don't have time to do it justice right now, but there is a great chapter I just wanted to mention. It's about the high-fat African game animals, which are disproportionately represented in many sites tied to paleolithic hunting.
This is an opportune moment to take another brief detour into the realm of archaeology, this time to look at views about the hunting capabilities of hominins who occupied sub-Saharan Africa between about 300,000 years ago and roughly 40,000 years ago, give or take a few millennia. For those not too familiar with
archaeology, in Africa this period of the Paleolithic is known as the Middle Stone Age (MSA). During more or less the same period of time, Europe and western Asia were inhabited by Neanderthals, and in these more northerly latitudes of the Old World the comparable part of the archaeological record is referred to as the Middle Paleolithic (MP). Richard Klein has written extensively about the hunting strategies of MSA peoples, focusing particularly on the faunal record from two well-preserved and widely known cave sites located east of Cape Town along South Africa’s Indian Ocean coast – Klasies River Mouth and Die Kelders.
Klein has argued for many years that MSA hominins lacked not only the technological know-how of the people who followed them during the ensuing Later Stone Age (LSA), but they also lacked the cognitive wherewithal. Interestingly, eland remains in these caves are central to his line of thinking, and hence the reason for this detour. And, as I have been doing throughout the book, I will let Klein speak for himself.
In contrast to the other ungulates, the eland in MSA sites include a large proportion of primeage adults, and the age profile has a catastrophic shape…. The most likely explanation is that MSA people had learned that, unlike most other large African bovids, eland can be easily driven, without much personal risk. An eland herd caught in the right position could be forced over a cliff or into a trap…. However, MSA people could not have driven eland herds to their death very often or the species would have become extinct, since its reproductive vitality would have been sapped by the continuing loss of a large proportion of the available prime adults. Not only did the eland survive, but there is no evidence that it became less numerous during the long MSA time span…
Thus, MSA people were probably not very successful at hunting eland, and this makes it especially interesting that eland is the most abundant ungulate in the MSA faunas. The clear implication is that MSA people must have been even less successful at hunting other species that are less common in the sites but were more common in the environment. In short, MSA impact on the large mammal fauna was negligible. By extension, it may be argued that LSA peoples, in whose sites eland and other species are represented more in proportion to their live abundance, probably took a higher proportion of game overall. In short, LSA people were almost certainly more proficient hunters. Klein (1987:36–37)
I think this argument needs to be turned on its head. Judging by the many quotes from historic accounts that I have already presented, all of which extol the virtues of the eland as the “game-of-game” in a land of fat-poor animals, the eland is precisely the animal that one should target if the animal is available and the hunters possess the means. If anything the abundance of prime-adult elands in MSA sites is testimony to just how good, and successful, they were as hunters, not evidence of their impoverished cognitive capacity. It is the LSA hunters that should be the focus of interest here. Why were they (as it would seem) compelled to concentrate more on the far leaner and smaller game, the prey that explorer after explorer considered inferior food, especially when they were short of adequate sources of carbohydrates or alternative means of acquiring fat? It seems far more likely that the hunters of the LSA were under some level of stress, either because they managed to overhunt the elands, or perhaps because environmental changes reduced the numbers of elands. All of this remains speculative, of course, but I think the one conclusion we can safely draw from this is that the presence or absence of eland in archaeological sites tells us nothing about innate cognitive capacities.
Incidentally, the abundance of prime adults, evidence that led Klein to postulate that MSA hunters may have driven groups of eland over cliffs or into traps (the “catastrophic” age profile that Klein refers too – that is, an age structure that resembles what one would observe in a living population) need not imply mass kills. Since the faunal assemblages are aggregates or palimpsests of countless individual hunting episodes, the abundance of adult animals in their prime is what one might expect if hunters often deliberately sought out animals that were at their peak in condition, but also now and then killed whatever eland came within their sights, regardless of age. It would be interesting to know what proportion of the adult eland at Klasies and Die Kelders were males….
Hmm, possible dissertation topic? What's so important about eland? Why would hunters target them?
An 18th century Swedish naturalist quoted in the book gives some clues:
This animal [“Cape-elk” or eland] has a great deal of fat, especially about the heart: from an old male which we gave chase to and shot, we got such a quantity of fine and tender fat, as we could with difficulty get into a box that would hold about ten pounds of butter. As at the commencement of our journey homewards through the desert, the hounds we had with us had unluckily devoured our stock of butter, a farmer, who still accompanied us, showed us how to prepare the fat from about the heart of the elk, and to use it for dressing victuals with and for eating on bread in the same manner as is generally practised with goose-grease and hogs-lard. The taste of it also was very similar to these, and to the full as good; and, indeed, if I may be supposed to have been able to form any judgment of the matter at a time when we were so sharp set, and in absolute want of any thing else of the kind, it was rather better. The breast is likewise extremely fat, and is always looked upon as a great delicacy. The flesh is universally of a finer grain, more juicy and better tasted than that of the hart-beest. Sparrman (1785:207–208)
Speth has great information on early food containers where hunter-gatherers may have stored things like fat or boiled bone grease. Pottery may date back as far as 200,000 years, but it's also possible to store and cook with liquids in skins and other containers that would not be present in the record. He also takes down the common use of the San (bushman) as Paleolithic proxies.
I'll post more about this book soon. I've been very busy with school, but luckily this is what I study so I have ample fodder for posts now. I feel very bad for people who don't have access to this things.
It's possible they will take old books that are outdated and try to push their own rather narrow conclusions. Altough you don't need to have research journal access to find that Boyd Eaton thinks his own conclusions were wrong (though Konnor is still holding out):
Meanwhile, paleo eating continues to evolve. In 1985, Eaton and Konnor allowed foods like skim milk and whole-wheat bread. Konnor still thinks that was the right call, and believes his original concerns about fat were prudent. “You can’t just go to the supermarket and buy meat loaded with fat and say you’re doing the Paleolithic diet. You’re not.” Animals of 10,000 ago, Konnor says, were less fatty—so we must compensate by eating leaner meats, and less. Eaton has gone the other way. He says he had failed to consider the contribution of non-muscle meat like brain and fat depots, and thus underestimated the amount of fat we need. “It makes me feel stupid!”
In full discloser, I don't think there is enough evidence either way to draw a conclusion about fat in the paleolithic and we are dependent on modern nutritional science to elucidate whether or not fat is healthy (or types of fat). I also am a big fan of the idea that evolution of human being is on-going and didn't freeze in lower-paleolithic Africa. I personally cycle low and high-fat, but do best on high-fat (I lose my period on low-fat, for example).