This blog is about the intersection between evolutionary biology and food. But also about practical applications, sustainable agriculture, and general tasty things.
I've written before on how the typical "paleo" paradigm didn't fix my digestive problems. That's because paleo divides things into good and bad in a somewhat arbitrary manner. The reality is that good and bad are relative to the functioning of your body and your individual biology. As Dr. Ayers said in his latest post:
This suggests that the problem is somehow in the intolerant person, even though there are no genes for food intolerance and very few cases of food intolerance result from an immune reaction. Food intolerance is actually the inability of an individual's incomplete gut flora to digest certain types of food.*
The question becomes whether or not you can figure out which foods you are intolerant of and then whether or not you can become more tolerant. Your malfunctioning gut bacteria probably don't care about whether or not a food is "paleo" or not.
This becomes clear now that an army of paleo cookbooks have been published that contain nut and coconut flours. My family has discovered the hard way that these flours can be quite harsh on the digestive system. My mother told me she reacted terribly to some coconut flour baked goods she made, but not to plain old bread. I found that I reacted to both about the same, which meant that both seemed to lead to cramping and bloating. That's not really surprising, since it seems fructans are my main enemy.
Almond and coconut are "paleo" ....why? Because they are not seeds (actually, they are technically seeds, which is pretty hilarious that people don't think of them as such) and grains? Even though there is ample evidence for seed and grain consumption in the actual Paleolithic. And almond and coconut share many of the properties that some "paleo" advocates claim are the problem with grains, such as high levels of phytic acids and potentially-reactive lectins and other proteins.
For example, Robb Wolf tweeted that he didn't think grains could be a "safe starch" because there are some papers on various immune-system reactions to them. But I can find papers on very similar reactions to our sacred cow. I'm sure in some parallel vegan circle-jerk twitterverse, Dr. Dean Ornish is tweeting those papers to confirm his follower's various biases, but as I wrote about sialic acid from meat, not everyone reacts this way. And in particular, I don't think healthy people are as likely to have such dysfunctional immune responses to food, but Westerners raised on crap in a "hygienic" environment are very vulnerable.
My mantra is that a sick person can react to ANYTHING. And a very healthy person can tolerate a lot of terrible things. I always like to remember the story of Mithridates VI of Pontus, who was so paranoid about being poisoned that he took small doses of various poisons in order to accustom his body to them (hormesis perhaps). When he was defeated by Pompey, he tried to commit suicide by poison, but couldn't because he was immune to what he had on hand. So he had to have his bodyguard execute him by sword. He is immortalized in an excellent poem by A. E. Housman
There was a king reigned in the East:
There, when kings will sit to feast,
They get their fill before they think
With poisoned meat and poisoned drink.
He gathered all the springs to birth
From the many-venomed earth;
First a little, thence to more,
He sampled all her killing store;
And easy, smiling, seasoned sound,
Sate the king when healths went round.
They put arsenic in his meat
And stared aghast to watch him eat;
They poured strychnine in his cup
And shook to see him drink it up:
They shook, they stared as white’s their shirt:
Them it was their poison hurt.
–I tell the tale that I heard told.
Mithridates, he died old.
– A. E. Housman, A Shropshire Lad
I love the line "the many-venomed earth" and it's one that has struck with me often as I study science, along with Tennyson's "Nature, red in tooth and claw" from In Memoriam.
Interestingly, through self-experimentation I've found that I do not just OK, but much better eating things made with rice and certain pseudograins. My skin improves when I eat finely sifted fermented buckwheat (a pseudograin) and I have much more energy and digestive stability when I have some rice in my diet.
I also think some of these gluten-free grain-free things are pretty much torture to cook, requiring all kinds of fruit/vegetable purees or five million eggs to produce something even somewhat appetizing. And I don't have any particular interest in eating things that are only somewhat appetizing unless they are exceptionally nutritious.
Sometimes I get asked what my diet is like and that's a hard question to answer. I'll go through periods where I cook some particular ingredient over and over again, and then I kind of forget about it for awhile. It's like that with buckwheat for me. Perhaps the craving has something to do with buckwheat being particularly rich in magnesium?
Lately, one of my favorite meals is buckwheat pancakes with delicious toppings. My method for making buckwheat pancakes is that I sift the flour and then soak it for a day in sour whey or sour cream. Then I mix in an egg and cook it in fat of some sort. This one I topped with bacon-wrapped elk, REAL lingonberries (not the jam from IKEA, I bought them frozen at Erickson's Delicatessen and they are very sour, so they work very well with savory dishes), and seaweed.
* I also agree with Mat Lalonde that reactions to specific proteins can be an issue, though the two things are somewhat interconnected
I've been listening to a little bit of the Paleo Summit and today I listened to Nora Gedgauda's presentation on "safe" starches. You can still catch it for another hour or so I think, but let's just say it wasn't my favorite presentation in the world.
If you've read this blog long enough, you know I have an interest in fiber. One thing that is interesting about early "paleo" books, Boyd Eaton's 1989 The Paleolithic Prescription, is that they recommend an absurd amount of fiber. That's partially because some estimates of fiber intake based on fossilized poo, known as coprolites, were just simply absurd, as high as 150 grams a day, which no known human culture even approaches. So I've spent a little time arguing against that, because the coprolite analysis for fiber isn't even very accurate in the first place.
So when I hear more info about coprolites, my ears perk up, particularly if it's totally outside the realm of anything I've ever heard. In Nora's presentation she cites a paper that she says shows that a wide-ranging sample of paleolithic coprolites shows that they weren't eating any plants. What?
So I tracked down this paper. Turns out it's not a paper, it's an article in a magazine, though I admit that Scientific American is definitely a quality magazine.
So your homework assignment for the night is to read the "paper" and figure out where it says any of what Nora says at all
Spoiler: it doesn't say any of those things at all. Nope, none. Hilariously, a lot of the article is in fact devoted to the Pecos basin hunter-gatherers I've written about, but they didn't live in the Paleolithic and they ate a massive amount of various plants.
Bonus point: find ANY paper that supports what Nora says.
Nora is trying to fight Paul Jaminet's mainly bio-chem based arguments about starches with anthropology, but she doesn't have much ammo. The idea that homo sapiens was forged in some kind of arctic ice age goes against all the existing genetic and archeological evidence that exists. When we are talking about the influence of the last ice age on homo sapiens, it's more about forests dying off and becoming grasslands and savannas, than people plunged into some polar darkness in which they could only eat mammoth.
Nora then cites the isotopic evidence. Nope, she doesn't cite one of the many papers on the subject, she cites Dr. Eades, who is an MD, not an anthropologist. Probably because in those papers they try to make it clear that isotope analysis cannot tell us that ancient hominids were eating like foxes. It can simply tell us the trophic level of the protein consumed, which is similar to foxes in SOME cases, but we are not foxes. We are large-brained primates with the ability to eat a vast variety of foods, so the trophic level cannot rule out other foods being consumed, nor can it tell us the amount of protein in the diet. John Hawks put up an assortment of posts on isotopic analysis in response to an email from Chris Masterjohn.
As for the ketogenic babies, I think babies are really the reason that most humans can adapt better to ketosis than most other mammals, which I learned from Stephen Cunnane's excellent book Human Brain Evolution: Influence of Freshwater and Marine Food Resources:
There are two key advantages to having ketone bodies as the main alternative fuel to glucose for the human brain. First, humans normally have signifi cant body fat stores, so there is an abundant supply of fatty acids to make ketones. Second, using ketones to meet part of the brain ’ s energy requirement when food availability is intermittent frees up some glucose for other uses and greatly reduces both the risk of detrimental muscle breakdown during glucose synthesis, as well as compromised function of other cells dependent on glucose, that is, red blood cells. One interesting attribute of ketone uptake by the brain is that it is four to fi ve times faster in newborns and infants than in adults (Robinson and Williamson, 1980 ; Cremer, 1982 ). Hence, in a sense, the efficient use of ketones by the infant brain means that it arguably has a better fuel reserve than the adult brain. Although the role of ketones as a fuel reserve is important, in infants, they are more than just a reserve brain fuel – they are also the main substrate for brain lipid synthesis (see Baby Fat – The Reserve for Brain Lipids section).
I have hypothesized that evolution of a greater capacity to make ketones coevolved with human brain expansion (Cunnane, 2005a ). This increasing capacity was directly linked to evolving fatty acid reserves in body fat stores during fetal and neonatal development . To both expand brain size and increase its sophistication so remarkably would have required a reliable and copious energy supply for a very long period of time, probably at least a million, if not two million, years. Initially, and up to a point, the energy needs of a somewhat larger hominin brain could be met by glucose and short - term glucose reserves such as glycogen and glucose synthesis from amino acids. As hominins slowly began to evolve larger brains after having acquired a more secure and abundant food supply, further brain expansion would have depended on evolving signifi cant fat stores and having reliable and rapid access to the fuel in those fat stores. Fat stores were necessary but were still not suffi cient without a coincident increase in the capacity for ketogenesis. This unique combination of outstanding fuel store in body fat as well as rapid and abundant availability of ketones as a brain fuel that could seamlessly replace glucose was the key fuel reserve for expanding the hominin brain, a reserve that was apparently not available to other land - based mammals, including nonhuman primates.
But I don't think that means it's optimal for adults. If anything, it's possible adult's ability to be in ketosis is a relic from infancy. Perhaps that's why some people seem to do better on ketosis than others, because like lactase persistence, the persistence of that ability varies from person to person. But I don't really know, it's just an idea and unlike some people I don't claim to know what everyone else should eat.
As for the Inuit not eating plants, it's 2012 and I think there is enough information on the internet available, like my own blog posts, that put that misconception to bed.
No, but people take this stuff seriously, as you can see in the comments:
As far as Nora's presentation goes, it's backed up by more science and understanding of human physiology than any of the pro-carb messages I've seen.
If you want to listen to a better talk, I'd suggest Mat Lalonde's. I wish he'd write a book. We know paleo can work, science can help us figure out why and knowing why can help us target variations of the diet to individuals. I firmly believe that a successful diet involves acknowledging the normal distribution and trying to "pin the tail on the donkey" to find your place there (or your range dependent on other variables) through self-experimentation and other tools. It's clear he does that in his own life, so he's talking the talk and walking the walk. I do differ in opinion in that I have tended to think that issues with grains aren't issues with proteins, but issues with carbohydrate malabsorption. But I'm open to both ideas being right.
Most importantly, Mat calls us to be rigorous in our use of scientific evidence, which is something many other speakers at the Paleo Summit seem to be unable to do. Their readers, who do not have access to academic journals by and large, take them seriously without ever knowing the truth.
As for the idea that those of us who are skeptical of the anti-starch stance just being addicts, I really do laugh because I remember a comment a militant vegan relative of mine posted on the blog. He accused me of making up evidence for meat being healthy just because I think it's so tasty. Ha. Anyone who knows me knows that when I started trying "paleo" diets, I did not like meat very much, though I do like it now.
As for starch, the idea that I'd be addicted to the mediocre bland peasant-like tastes of things like cassava or green plantain is absurd. I really challenge anyone who thinks such things are addictive to go to their nearest ethnic market and purchse a true yam. Then boil it and eat it plain. Have fun!
If I promoted a diet based on what I crave, it would be based around caviar, bone marrow, and butter. Through, it is quite funny that all of those things are quite good for you.
Some folks have wondered why I still recommend Gary Taubes' books on my Start Here post given that I have been vocally negative about him lately. Yes, I have a problem with his attitude and frankly find him stubborn. But the truth is that his books changed my life. Without Good Calories, Bad Calories, I might still think that eggs, butter, liver, and cheese are bad for you. I might still think that fat makes you sick and fat. These foods have been instrumental in improving my health and thus my life. The fact that his carbohydrate hypothesis of obesity has attracted so much energy and attention is an unfortunate distraction from the fact that his books mount an excellent defense of fat. The idea that carbohydrates per se cause obesity is only being debated by a few silly reductionists. For those of us who have read extensively about other healthy cultures, that doesn't even begin to make sense. What healthy peoples have in common is the nutrient dense foods they eat, not their macronutrient ratios. The rest of us have moved on to more relevant issues, like how to have sexy hair, or awesome babies, and stuff like that.
The Dinka Diet is based around porridge and dairy, insulinogenic foods, why aren't they fat? (note that the Dinka have suffered in recent years from warfare and famine and probably no longer look like this. I didn't want to post the Kitavans, the Aka, or any high-carb tribes I've written about already for the sake of diversity. As for whether this is the "ideal" for men, you have to realize that some of body composition is genetic. The Dinka do not bulk up like other men, they are very similar to the Maasai in that way. It is possible that sexual selection is at work here, as this body type is considered very attractive to the Dinka. The Wodabe are an extreme example of this.)
More porridge eating fatties. Scotland now has one of the highest rates of obesity in Western Europe. Hint: it's not the porridge!
As for not getting fat, we could argue about what makes people fat all day, but it's clear that it's not sweet potatoes and plantains making people fat. It's clear that it's something about industrial food, which has the unholy synergy of caloric density, hyperpalatibility, and nutritional poverty, along with bundles of rancid vegetable oils, improperly vetted synthetic chemicals, loads of refined sugar, and other garbage.
Gary Taubes = Diglett
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.
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.
Anthony Bourdain is a food celebrity, author of Kitchen Confidential and host of No Reservations. Today Reddit posted an interview with him which has mysterious been taken down, but in it he mentioned his wife's all-meat diet. With the death of VLC celeb "The Bear", perhaps Ottavia Bourdain can carry on the torch. She does mixed martial arts. I don't think VLC works for many people, but for some people it provides the best results. As long as you are careful to consume organ meats and seafood, it can be effective, especially as a way to treat stomach disorders, though most people find that eventually they can add some carbs in.
Since she Tweets about meat-mecca Takashi, hopefully she is getting her share of liver and egg yolks.
This weekend I was reading Food and Western Disease on Friday and in the intro Dr. Lindeberg talks about why some starchs like yams might be OK since humans have such a long history eating them in our ancestral African homeland, whereas potatoes are a "new world" crop and humans have only been there for at the earliest 35,000 years ago. The problem is that when I see people saying their yam dishes are paleo and potatoes aren't...they are not really eating yams, but sweet potatoes, which are Ipomoea, a NEW WORLD crop. Maybe Ipomoea has fewer anti-nutrients, but from a botanical viewpoint anti-nutrient composition is independent from ancestral history. There are many foods we have been eating a very very long time like cycad that are far more toxic than cultivated vegetables. Humans have bred vegetables to be less toxic in most cases.
This is "New World"
True yam (Dioscorea) is quite different from sweet potato. Most are quite large, have scratchy skin, and a white flesh, though purple yam (Ube) exists too.
I bought one at a local market recently. They are quite cheap here because they are popular with many immigrant populations and are imported in large quantities. But after buying it, it languished some time on the counter because it was kind of intimadating. It just looked large and grizzley...I decided to try it first made by the experts- Nigerians. Luckily there is a Nigerian restaurant near me.
Nigerians typically serve yam as "fufu," which is boiled yam pounded into a dough, though there are cassava and corn fufus too. The fufu I had was pretty bland and starchy. I don't know if I'll be seeking out African Yam in the future. I really liked the fermented cassava fufu though. It had a wonderful sour taste.
I was going to write about how all the paleo folks eating sweet potatoes and thinking they are so authenic are a bunch of posers, but then I realized I might be endangering all the paleo manhood. You see, yams actually have much scarier plant chemicals than sweet potatoes or potatoes. For example, researchers looking at the unusual incidence of twins in some Nigerian towns found that chemicals in yams might be to blame
In 1996 Ugwonali went to Nigeria on a Downs fellowship to begin his research. After analyzing age, socioeconomic factors and other variables, Ugwonali focused on diet. Demographic and scientific studies conducted in the early 1970s pointed to white yams as the culprit in the mystery of multiple births in southwestern Nigeria. Ugwonali interviewed people about their eating habits and made his own observations. “We suspected environmental factors,” he said. “The only factor that ended up being different from the ones we controlled was yams.” In laboratories at Yale and in Nigeria, he fed rats a diet of yams and saw the average size of their litters double from about four to about nine.
“Our hypothesis is that yams act as anti-estrogens,” he said, noting that he hasn’t investigated the precise chemical link between yams and fertility and has yet to isolate an anti-estrogen from yams. Anti-estrogens fool the brain into thinking there is insufficient estrogen, causing it to release more of a hormone called gonadotrophin and increase the ovulation rate, he said.
The "most paleo sounding yam" the wild yam (Dioscorea villosa), is even more questionable, since in folk medicine its extracts are thought to be estrogenic and used for "bust enhancing." In some studies they have been shown to change sex hormone concentrations (though other studies show it is ineffective)
After yam ingestion, there were significant increases in serum concentrations of estrone (26%), sex hormone binding globulin (SHBG) (9.5%), and near significant increase in estradiol (27%).
So yeah boys, keep eatin those "paleo" "yams." They taste much better and won't give you man boobs.
When I saw these photos of an "uncontacted" tribe it became very clear to me that we must contact them as soon as possible. As you can see in the above photo, they are consumers of cassava, which is a starchy tuberous root. Someone has gotta tell them that all that starch will make them obese.
In all seriousness, this morning I got an email from Maria Rainer, one of many content farmers who generously offer to write "guest posts" for my blog. I totally understand her plight, since the modern university scam is to give a massive percentage of undergraduates degrees in English regardless of the fact that only 10% have writing talent and there are almost no openings in writing jobs that require any sort of craft. The rest of the English majors are forced to work in debt collecting, retail, or content farming. I'm not judging. After all, I'm even more of a sucker since I thought I was getting a useful degree, but it has really only served me in blogging. OK, actually I am judging and would appreciate if content farmers would refrain from contacting me.
I shall not grace one of her pieces with hits, but her resume she sent me includes one on how to eat vegan AND paleo. It recommends you avoid coconut since cavemen didn't live in Hawaii (a simple Google would inform her that coconuts aren't even native there!). It mentions how some modern hunter-gatherers get over 50% of their calories from plants, but again enters major fail territory by saying NO to starchy tubers. Guess what plants those hunter-gatherers are getting their calories from? Hint: it's not lettuce.
Starchy tubers are exactly what most hunter-gatherers (or horticulturalists in this case I suspect) rely on for plant foods. The bitter cassava seen above is perfect because it can't be eaten raw by animals, but humans can soak out the cyanide and consume it.
Lately out of curiosity I've been experimenting with tropical starches. This weekend I made some sweet cassava (cyanide free) and it was surprisingly easy. The peel came off quickly and it boiled much faster than potatoes. It soaks up sauce wonderfully.
Another starch Chris and I tried this weekend was plantains. I'm surprised that more paleos aren't into it. Maybe it's the carbophobia. But it has the best of a banana and a potato. If you are eating bananas, might as well switch to green plantains since they are lower in sugar. And they get crispy in leftover bacon grease MUCH faster than potatoes and taste nearly identical. There are also sweet plantains, which make a decent dessert dressed with coconut oil and cinnamon.
Next up: The malanga(cocoyam), taro, and true yam. The true yam intimidated me this weekend. It's lumpy and unfriendly, though not as menaching as the cocoyam. I might have to check out a local Nigerian restaurant to learn how to do it the right way.
If you are venturing into paleo-izing a vegan diet, these starches are worth checking out. Personally, I feel quite good when I have a little starch with my meat.
Any tips would be appreciated!
Great, a new pop-sci treatment of an anthropology paper that your Aunt Maude will forward to you with the implication that you should eat her whole wheat pancakes next time you visit. The article portrays this as some kind of ground-breaking research that totally changes our view of the paleolithic.
So what's the deal with this study? Now that I'm wormed my way into academia again somehow, I read the paper. They found something that looks like a mortar and pestle with some evidence of starch residues.
The title says flour, but that's not the good old white flour your Aunt Maude is thinking of. Of the nine species mentioned, one is a seed, the rest are roots and rhizomes. That ground starch has been used by humans since the upper paleolithic is not really news. Famous anthropologist Richard Wrangham who wrote Catching Fire has been writing about the role of cooked starch in the Upper Paleolithic for quite some time. In the Upper Paleolithic it might have spurred population increases that eventually led to early settlements like Gobekli Tepe. There has been selection for genes like AMY1 which allow for better starch digestion.
I think isotope studies are a little more accurate than a few as the paper admits "poor preserved" plant remains. And the evidence is that the protein in the paleolithic diet was mostly animal protein.
Find the whole wheat...
I've had cattail and it's not bad, though a pain in the ass to gather and process. If you want something similar chestnuts are another starchy paleo-ish food, which by coincidence I ate today. So if it makes you feel more accurate have some yams or chestnuts alongside of your steak. But steak is king.
One common question is "What the difference between paleo, primal, and Atkins?" So I made this chart. But in some ways it's very hard because as the science becomes stronger, there has been a strong convergence between the three. For example, many Atkins devotees have realized that they just don't do well on low-carb Frankenfoods. And Cordain has come around with regards to saturated fats.
I put markers on for the most popular "gurus." Kurt Harris at PaNu basically espouses a unprocessed carb-restricted version of paleo which could pass for Atkins. Mark Sisson advocates a fairly laissez-faire approach with the goal basically to avoid the worst foods that aren't on this diagram anywhere. Robb Wolf recommends different things for different goals as I wrote in my review. Loren Cordain is mostly about specific foods and is still down on dairy and nightshades. I guess now that he's writing more and more about how bad those are, they might end up next to dairy in this diagram.
Where am I? I guess the closest to what I do it Sisson + Wolf. I'm moderate carb and do eat some dairy sometimes. Where are you? Quibbles? Questions?