This blog is about the intersection between evolutionary biology and food. But also about practical applications, sustainable agriculture, and general tasty things.
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.
It's interesting to compare Meat : A Benign Extravagance to the Vegetarian Myth. On the surface both challange animal rights dogma, but Meat is primarily a book about economics and is far more rigorous than the Vegetarian Myth. Unfortunately one thing they have in common is that both authors adhere to philosophies that I would deem somewhat noxious to put it lightly, though Fairlie's in a bit benign.
Behind both of their philosophies is the idea that somehow humans are bad for the planet (some even call us an "invasive species"). Our pleasures are irrelevant, we are a scourge upon the goodness of nature. I first heard about Keith from a lecture given by her good friend Derrick Jensen, a misguided character who would welcome a new Black Death and advocates violence as a way to solve environmental injustice. Her association with that movement is unfortunate. Luckily Fairlie is more an acolyte of a secular form of neo-puritanism advocating the idea that we should live very simply, perhaps similar to 15th century European peasants, spurning "luxuries" and only having a few "extravagances."
But what are luxuries and what is extravagant? One lesson I've learned from studying paleolithic cultures is that humans don't really need very much. Bushmen get along quite well without houses or possessions of any kind. This family in Chad gets by with a tent, a few animals, and meager rations of gruel. Most vegans spurning meat as an arrogant luxury go home to well-lit artificially heated apartments. Why are those OK? I don't know. The whole thing seems arbitrary.
Even a ecoconscious vegan's life in the US seems extravagant compared to this family in Chad. This is their food for an entire WEEK. Their housing and clothing are very simple too.The OED says one of the meanings of extravagant is " 7. Exceeding the bounds of economy or necessity in expenditure, mode of living, etc.; profuse, prodigal, wasteful." The word comes from "medieval Latin extrāvagāt- participial stem of extrāvagārī (or extrā vagārī) to wander, stray outside limits, < extrā outside + vagārī to wander. "
So from the outset, by calling meat extravagant, we establish Fairlie as a complex character. We won't find him at either an animal rights ralley or the local Argentine steakhouse. He's kind of like an old school hippie.
It's funny because in the end people calling things luxuries are often the most arrogant. Last week I had a conversation with a vegan on a blog about The Heifer Project, which provides families in developing countries with livestock. Vegan dude was angry because Heifer sponsored a study that seemed to show that children fed animal products in developing countries did better. According to him "let them eat tofu!" Well, if folks want to chose a bicycle tofu press over a goat, that's find by me. But I suspect they won't. But that's not the point of vegan dude's views. Vegan dude thinks he knows what's best for everyone. I don't know what's best for everyone, though I suspect that goat milk is better for children than tofu. So in the end I think it should be up to people in Sudan to make that choice for themselves. Too bad the world is full of people who want to make choices for other people.
When I was a child my little sister and I sometimes fought bitterly. One day we were fighting over some candy and my mother was so frustrated that she said "Well, if you children can't share it equally, none of you can have it at all!" Besides the obvious lesson here that children who are given candy are liable to behave badly, this reminds me of some common positions in environmental debates. Namely that (insert food or agricultural practice) is bad because it can't feed the world. Sure, feeding the world is an admirable goal, but isn't it a little silly to assume that there is one system that will feed the world perfectly?
And yet,this is taken very seriously in environmental debates. I hear again and again how terrible organic is because it can't feed the world. Or how terrible meat is because of the same. It almost becomes nauseating. Hasn't macroeconmic reductivism caused enough problems in our world?
Meat tries to answer some questions about whether or not meat is inefficient, but in the end you end up with what most of us localists already knew: different production systems are appropriate for different places. There is no one magical system that's going to work everywhere. People should be free to chose the system that works for their own land.
With that, it's still interesting to inject some numbers into the debate. Agricultural production is more complex than people would give it credit for being.
Some animal rights environmentalists would have us think that when you raise livestock you are taking food that humans could eat and wasting it on animals, who convert feed to meat/dairy/eggs inefficiently.
If you've ever had pets, you might notice that animals will eat things that we won't. In the old days of small farms animals served primarily as a way to inedible things into food. Cows can eat fibrous waste products and forage on land impossible to till. Pigs can eat well…pretty much anything (haven't you seen Snatch? *spoiler you can feed humans to pigs!*, wild boars are omnivores). Chickens can eat kitchen scraps.
Some of the waste resources animals can turn into food include
1. spoiled food
2. byproducts from milling, oil pressing, slaughterhouses
3. foods that humans spurn (bruised apples)
Animals turn these things into meat, milk, eggs, and manure. Fairlie calls this level of animal production, that which is a byproduct of plant production rather than as a primary product, "default livestock." I would personally quibble with that, as it reflects an agrocentric view of things that ignores nomadic pastoralism as a potentially ecological livelihood in certain situations.
Vegans sometimes call milk "liquid veal" since veal production is an inevitable part of milk production (though through science this might be eliminated in a future through cheap sex selection). Turns out that with that logic, most vegetable oil is liquid meat! The meal left over from vegetable oil processing is a highly profitable part of that industry because of its value as feed.
One of the things livestock provide is fertilizer from manure. Of course veganic (livestock completely without domestic animals) proponents could argue that some of the waste we are talking about could be composted and turned into fertilizer that way. Fairlie examines some current veganic farms and it turns out some of them do quite well, but others don't. As always, it seems that the ideal system varies from land to land.
The idea that land taken out of production by switching to more efficient food systems would be used as habitat never made sense to me. What are the odds that a farmer who needs less land will let the excess go feral? Odds are that it will be sold and turned into a mall or subdivision, which is what has happened with increased agricultural efficiency in most of the US.
Of course Fairlie and most animal rights folks aren't too concerned with that because they are usually advocates of governmental inventions. Which is ironic since Fairlie discusses quite extensively the havoc created by regulatory capture (when industries lobby for laws that benefit mainly them) and misguided policies. One of the most hilarious is the USDA law that hamburger can't be cut with pork fat. Pigs produce tons of excess fat, whereas grassfed cows don't. Why not make some appetizing burgers using both? The fact it's illegal has created demand for fattier feedlot cattle.
Other more insidious laws are those in response to animal and human diseases. Mismanagement of animal waste has led to several food poisoning outbreaks, such as the spinach e. coli debacle. Laws created in response have discouraged manure as fertilizer and the presence of animals on vegetable farms, which is a shame since properly managed animal manure is an asset.
Without this, one much purchase synthetic fertilizer or set aside large amounts of land to grow green fertilizer.
Some other problematic regulations were created in response to mad cow disease, which banned the feeding of slaughterhouse wastes to livestock. This is unfortunate because slaughterhouse wastes are perfectly appropriate for pigs, who are natural omnivores. Fairlie says this is a result of the "nanny state" but seems to call for regulations when they fit his ideology, which is a shame.
Because of such regulations manure and inedible animal parts have become a liability rather than an asset, though the livestock industry is still remarkably efficient.
The best parts of this section are those in which he dissects numbers thrown around by various animal rights ideologues. In my opinion those numbers are nothing but veils on a philosophy that's at its core about reworking our system of morals to turn them against humans, but either way most of them are wrong. The most amusing one is the idea that one kg of beef requires 100,000 liters of water to produce. Turns out that number is a bit of accounting gymnastics that would make any product seem inefficient, because it takes into account ever scrap of precipitation that falls upon the area of land a cow might occupy. Hmmm. Guess someone didn't learn about opportunity cost. The rain that falls on grassland isn't going to be collected and sent to people suffering from droughts in Africa in the absence of cattle.
This book is enormously dense and I feel like I haven't done this section enough justice despite having written quite a bit. I'd love to take questions from other readers. Please post in the comments or at our facebook group.
Wil asks "Fairlie talks about default/sustainable production and calculates an individual's "fair share" of total world meat production. Is it unethical to eat more than this "fair share"? Can you justify eating more than your "fair share"? How does population growth play into the equation? Are we obligated to help feed the world? Are we obligated to slow/halt population growth?"
In my opinion population growth is another localized issue. The book The Coming Population Crash is one of the few that treats it rationally and not as if humans are a terrible scourge upon the Earth. The truth is that some countries have more people than is optimal and others have less at this point in our history. Barring total immigration reform, this makes population issues fairly local.
As for the areas that may have optimally high populations, we have a well-accepted model called the demographic transition that posits that during development populations growth increases, but then decreases as having lots of children is increasing dis-incentivized. Women reading this from the comfort of first world countries will understand this quite well. How many of us can afford to have five children?
It also seems odd for an advocate of local food to calculate a fair share based on global factors. Unless you are a radical communist that believes everything should be equally distributed, it makes more sense to focus on valuing externalities properly to make the price of meat reflect its true toll on the environment and then allow people to make purchasing decisions based on their own desires. Let's say Fairlie is in charge of policy and decides to give me a meat quota for the month. I still have the same income. I might make even more unsustainable purchasing decisions in that case, like using the money I used to use to purchase grassfed meat on pretty dresses.
A major problem I just mentioned is improper pricing of meat because of subsidies and other distortions caused by the fact that we assign no value to many natural systems. It shouldn't be free to dump waste in an ocean you don't own.
Discussion questions from me:
1. What does extravagant mean? What do you think Fairlie means by it? What does it mean to you? What foods do you consider extravagant?
2. Should we use policies and regulations to reduce meat consumption to a default level? Do you agree with Fairlie's definition of default?
3. At what point are regulations part of a "nanny state?"
More blog posts:
Two exciting tips!
You may wonder why I, as someone who does not consume milk, would care about The Raw Milk Revolution. But this book has important implications for anyone who eats outside the mainstream. While I do consider raw milk a relatively risky food, I think it should be up to individuals to make the choice whether to consume it or not. As far as the argument that children can't make that choice, are we going to prosecute every parent that feeds their child potentially deadly food? I don't think the government has enough money to go after all the parents who feed their children massive amounts of sugar. Besides that, this book makes the point that illness from raw milk is very very uncommon. Why is the government spending massive amounts of money going after small farmers and not the large companies that poison millions every year?
If you think of any more, please email me at mgmcewen @ gmail . com