Back when I was writing the Hunter Gatherers and Health series of posts, I became aware of a book by Dr. Bill Schindler called Eat Like a Human. Schindler is an anthropologist with an extensive background in cooking and food preparation. He studies traditional food preparation techniques, including recreating hunting and gathering methods from prehistory as part of experimental anthropology. I didn't really have the time or space to do the book justice at that time. I've since read it, so let's have a look.
Introduction
The core message of the book is that humans didn't evolve to eat practically any of the foods we eat.
To expand on that a bit, while over long periods of time many animals evolved biological mechanisms allowing them to digest certain foods, humans took a different tack. We invented various means of processing our food to make its nutrients bioavailable and nontoxic.
That means while most animals had to co-evolve with their food sources over millions of years, humans could make practically anything edible anywhere in the world once they figured out how to process it correctly. And thanks to our culture, once those processing techniques were discovered, they could be passed down from generation to generation1.
That's really important. It's the reason why 1.) humans could survive even when their primary food sources became scarce. That's why we managed to survive all the multiple climatic upheavals which condemned many other species to extinction. When one food source became unavailable, we could simply pivot to another. If terrestrial mammals became scarce, for example, we could pivot to seafood or nuts or tubers.
And 2.) it allowed us to survive in practically any environment on earth. Humans could move into a completely new territory and exploit its resources because we didn't have to spend thousands or millions of years co-evolving with the prevailing environmental conditions and local food sources like other animals. We could just manipulate the environment to meet our needs and find exploitable food resources to process and make suitable for consumption. That's how we became such a highly successful "invasive species."
When we think of the story of humans and their tools, it’s really those two things that allowed us to take over the planet. Everything else sort of derives from those. Eventually we started manipulating foods at a genetic level through the process of artificial selection. Sometimes this process was intentional; sometimes not. But it eventually led to fully-fledged domestication of food and animal resources. Unlike wild foods, domesticated plants and animals are codependent—they cannot survive without us.
Another way to say this is the externalization of food processing. Animals have built-in biological mechanisms to process the foods they eat2. Often these involve naturally-evolved enzymes or symbiotic bacteria. The classic example is ruminants. The cellulose in plants is not easily digestible. When ruminants eat it, they send it to one of their four stomach chambers--the rumen—where it is fermented. Once that's done, the nutrition is available to the animal and it comes back up as "cud" to be chewed and digested. The cud is basically a "processed" form of the raw food.
Humans use a similar strategy, but we do it outside the body. The most fundamental example of this is, of course, the use of fire. Cooking essentially predigests our food for us, making its nutrients more bioavailable and detoxifying it in some instances. This, in turn, led to anatomical changes (smaller teeth and jaws, shorter intestines, etc). We can't even survive on a 100 percent raw food diet without modern technology and supply chains (and even then it's nigh impossible). Since then, we've massively expanded our repertoire. Schindler describes how the techniques used to make sourdough bread, for example, mimic the biological mechanisms by which birds can digest grains and seeds.
When we consider the fact that humans didn't evolve to eat practically anything we eat today, that leads us to ask a very important question. It is this question that Schindler starts his book off with and frequently returns to. In Schindler's formulation, the question is not so much what we should eat, but how we should eat it. The way we process food has different effects on our body.
Schindler argues that all of the current fad diets which try to specify which foods you should eat and which foods you should avoid are missing the point. The real question, based on his research, is how we should process foods to make them maximally nutritious for us? In light of this, we see that is not the proscription or prescription of certain foods or food categories that makes a healthy diet; rather, it is how they are processed. As Ran Prieur noted, "Whatever food you think is bad, you can find populations in the past who ate worse than us, and did not have a problem with obesity."
The reason every culture on earth could eat "forbidden" foods and not become unhealthy or obese is because of how the foods were harvested and processed rather than any particular food they ate or didn't eat. That's why focusing on which foods hunter-gatherers eat, rather than how they’re processed and what their nutritional profile is, leads us down a blind alley and acrimonious "diet wars" that lead nowhere.
The harsh reality is that biologically speaking, we have no business eating almost any of the food that we consume...How we overcame these physical and biological deficiencies and learned how to eat is the story of how our ancestors became human both culturally and biologically. Simply put: We developed technologies to do outside of our bodies what other animals do naturally inside theirs. Through serendipity, imitation, innovation, or some combination thereof, we created tools and behavior patterns that allowed us to access foods from our environment that otherwise would have been unavailable to us—whether physically or biologically—and we learned how to make them as safe, nutrient-dense, and bioavailable as possible for our weak, inefficient bodies before we ate them. The quest for safe, nourishing foods drove everything we did. (p. 13)
(With that in mind, it may make sense to avoid certain foods and food categories in modern diets if they are processed in ways that are not optimal—or even harmful—for us. Schindler doesn't talk much about this, preferring to focus how to make foods we do eat maximally healthy for us, but I will return to this topic later.)
Plants
If there's one thing we can all agree on, it's that plants are super-healthy and we should be eating as many of them as possible, right? Plant-based diet, eat the rainbow, and all that. Not so fast, says Schindler.
It turns out that plants don't want to get eaten any more than animals do. But since they can't run away, what they do instead is produce numerous chemical compounds to discourage and prevent animals from consuming them. Plants produce biological compounds known as allochemicals to deal with pests, diseases and fungi in addition to larger predators.
In some cases, these compounds are relatively harmless. In other cases, however, certain plants may literally be deadly if not processed correctly. But even relatively benign plants have can have harmful effects if eaten in large quantities for long periods of time. Toxins can build up gradually and cause damage. In reality, we're not designed to eat plants any more than any other type of food! This was certainly eye-opening to me.
The classic example of this is manioc—also known as cassava or yucca—which is a staple food for over 700 million people worldwide. It contains extremely toxic cyanogenic glycosides which are a form of cyanide and must be processed adequately to make the starchy root safe to eat. Most grocery store varieties are "sweet manioc" which has been genetically altered to produce less toxins, but is also less nutritious as a result (a recurring theme in plant modification). The wild form is still consumed all over the world, however, and those toxins mean that it has a nearly 100 percent crop yield. Cereal grains and maize (corn) are other examples that get their own chapters later on.
Manioc is also a vivid illustration of the point above. It's native to South America, which—aside from the islands of the Pacific—was the last place to be colonized by man. Yet people there were able to successfully use this poisonous root as a major source of nutrition because we learned how to detoxify it and make it edible. Today, we can even grow it in tropical and subtropical regions far from its South American homeland, feeding millions of people in the process.
Even the humble kidney bean can be deadly if not processed correctly. Red and white kidney beans contain a lectin known as phytohemagglutinin. Eating as few as four or five soaked but raw kidney beans can trigger nausea, vomiting, diarrhea and abdominal pain. Kidney beans must be detoxified by soaking—ideally in a slightly alkaline solution—and cooked to make them safe to eat. Lectins found in plants like legumes can inhibit our bodies' ability to make use of calcium, iron, phosphorous and zinc, and lead to inflammation. Certain plants such as grains, seeds and legumes in their raw, unprocessed state can actually prevent our bodies from absorbing nutrients correctly.
The chemical compounds found in plants also have medicinal value. Many of our medicines—most famously aspirin—derive from compounds discovered in plants. With the destruction of the Amazon rain forest, many of these plants are becoming extinct before we can even discover them. Certain plants produce neurotoxins that the natives of South America used for hunting and fishing. And, of course, the natives of South America somehow managed to discover potent psychoactive compounds in native plants which they used to make Ayahuasca.
The pharmacopeia of plants means that they are powerful resources for humans for many different uses including food and medicine. But it also means that plants are not the miracle health food we've been led to believe. That doesn't mean that plants aren't good for us, or that we shouldn't eat them. But just like every other type of food, plants need to be eaten in moderation, in season, be part of a varied diet, and processed correctly to remove the toxins and make their nutrients maximally available to us. Most plants require extensive processing, and traditional cultures around the world understood this. For me, this adds important context to the whole, "plants good; meat, dairy and grains bad" mantra of conventional wisdom.
Plants should scare the hell out of you...
Whether in grocery stores, or backyards, the hot heart of the Amazon basin, or the frigid barrens of the Arctic tundra, every plant on the planet contains toxins—among them phylates, tannins, cyanogenic glycosides, oxalates, saponins, lectins, and enzyme inhibitors. Some of them will kill you; some will just make you sick. Some won't hurt you at all, while others will build up—or "bioaccumulate"—in your body over time an cause issues later in life. Some of these toxins can be used as medicines, and some are actually good for you. But all plants have them.
Spinach, for example, contains oxalates, which under a microscope and in your body resemble tiny shards of glass. We are only now beginning to understand that many ailments commonly diagnosed as inflammation, fibromyalgia, and even pseudogout can be attributed to plant toxins like oxalates. Sufferers of kidney stones, for instance, are warned to stay way from oxalates, because they can cause more stones...when we eat the same vegetables year-round, rather than only when they are in season—for instance, when we eat asparagus, a spring crop, at Thanksgiving—even these very small amounts of toxins can build up in our bodies and do us harm3.
Toxins in plants are designed to protect the plant; they are nature's pesticides, herbicides and fungicides. An while we know that human-applied pesticides can be dangerous, it's eye-opening to note that pesticides produced by plants themselves actually account for 99.9 percent of pesticides that we eat. It's estimated that every American eats 1.5 grams of naturally occurring pesticides per day, which is about 10,000 times more than the amount of synthetic pesticides we eat. In other words, the plants themselves deliver more pesticides to our systems than what we spray on them...
Vegetables have been sold to us as the cornerstone of a lean, healthy diet, and they certainly confer health benefits. But they aren't nearly as good for you as our contemporary food system would have you believe. Plants were not put on the planet to feed us, nor are we biologically built to eat a vast majority of them. They are loaded with toxins and they don't easily give up their nutrition to our bodies. So if we are going to eat plants, we need to ask the right question: How do I make this plant as safe, nutritious and accessible as I can? (pp. 24-26)3
Over the years, many of the most harmful compounds have been bred out of plants by artificial selection. Most grocery store aisles contain only a handful of the plants that we’re capable of eating (the majority them being cultivars of Brassica oleracea). This means for a lot of foods intensive processing is no longer necessary. This has other unfortunate side effects, however, one of which is the fact that without their natural disease and pest-fighting compounds, the plants need to be sprayed with artificial pesticides to maintain crop yields. These chemicals find their way into our bodies.
Even more alarming is the fact that the plants we eat are steadily becoming less and less nutritious over time. The demands of ever-higher yields and transportability has lead to declining nutritional value, including a reduction of compounds that keep us healthy and fight disease. Declining soil health also plays a significant role in the reduction of nutritional content. Plants, once so beneficial to us, are getting worse and worse for us thanks to selective breeding, with more sugars and starches and less protein, minerals and vitamins4:
...through domestication and genetic manipulation, we've also reduced these plants' nutritional density, medicinal value, and flavor. The produce in our grocery stores is far less nutritious than its predecessors of even a few decades ago. According to a 2007 report by the Organic Center—spurred by a symposium at the American Association of the Advancement of Science—American agriculture's unwavering emphasis on increasing crop yields has resulted in a steady decline in crops' nutritional value...
In corn and wheat plants, higher yields have correlated to falling levels of protein (a 0.3 percent decline in every decade of the 20th century) and rising levels of starch (an increase of the same amount, 0.3 percent, over the same period). The report notes that...in 14 varieties of wheat grown between 1873 and 2000, when the average per-acre harvest more than tripled, the wheat's macronutrient content declined dramatically—for example, 28 percent less iron, 34 percent less zinc, and 36 percent less selenium over that period...Jo Robinson notes that the kernels of modern corn's ancestor, called teosinte, were 30 percent protein and 2 percent sugar. Compare this to contemporary varieties that are as high as 40 percent sugar. Robinson has noted that “eating corn this sweet can have the same impact on blood sugar as eating a Snickers candy bar or doughnut.”
Higher tomato yields correlate with lower vitamin C and lycopene, while cows produce more milk that's less concentrated with fat and protein...When Robinson compared six wild varieties of apples to six modern varieties, she found that the wild varieties had 475 times more phytonutrients. The Ginger Gold, a relatively new apple, has so few phytonutrients that it fails to even register on the scale. Yet a purple potato native to Peru has 28 times more cancer-fighting anthocyanins than common russet potatoes... (pp. 28-29)
Fruits and vegetables are less nutritious than they used to be (National Geographic)
Schindler recommends: 1) foraging for wild plants that have not been domesticated. This can be done anywhere, but it takes a bit of skill; 2.) growing heirloom varieties of plants that contain more nutrients than those found in supermarkets; and 3.) eating plants in season. Of course, the first two steps will naturally encourage the third. Eating seasonally means that the toxins found in various varieties of plants will not build up as much in your body since you are switching between different varieties at different times of the year just like our ancestors did. Foraging for wild plants is, of course, how our hunter-gatherer ancestors got most of their food.
Foraging lets us source the highest-quality, most nutrient dense plants possible while ensuring that we are acting hyper-seasonally, bonding with our environment, and observing the consequences of our actions. It's the very antithesis of walking into a grocery store and plucking a waxed Red Delicious apple of plastic bag of lettuce from a shelf. Instead, it requires all of your attention, research, and senses. (pp. 31-32)
Here are some common wild varieties of plants:
Dandelion
Garlic mustard
Wild spinach, aka. lamb's quarters
Purslane
Chickweed
Fiddlerheads
Schindler is a big proponent of fermentation to make the nutrition in plants maximally bioavailable to us and to provide us with beneficial probiotics. There are recipes for fermented carrots, fermented roasted peppers, and what he calls "Lacto-chips and fries," which is based on a traditional fermentation process that the Quechua people of Peru use on their their heirloom potatoes (known as tocosh)
Animals
Humans have hunted and eaten animals for over a million years. But the way we consume them today has changed dramatically.
When hunter-gatherers made a kill, they consumed every part of the animal: the meat, the fat, the bones, the organs, the ligaments, the hoofs, the pelt, the horns—every part was used in some way. Even the milk from lactating animals was consumed as Schindler informs us later in the chapter on dairy.
By contrast, today we basically consume only about half of the animal. Even more remarkably, we throw away the most nutritionally dense parts! What ends up in the grocery store is approximately only 50 percent of a cow by weight, and only 55 percent of a pig. And the parts we discard are not only the most nutritious in terms of vitamins and minerals, but the nutrients are the most bioavailable to us even without cooking! Liver, for example, carries more protein, vitamins and minerals and less fat than the same portion of lean ground beef. Therefore, as Schindler puts it, we should be eating "less meat and more animal."
By focusing only on meat—and especially lean meat—we have excluded nutritious, high-quality animals fats, organs, and other offal from out diets, and these are the most nutrient-dense, bioavailable foods on the planet for our human bodies...This emphasis on meat has warped our concept of what a truly healthy diet is in terms of animal protein. We are deathly afraid of fat. But high-quality animal fat literally helped fuel our most profound evolutionary advances as humans.
Humans began eating meat by scavenging from dead animals whose viscera—the organs, blood, and fat—had already been stripped by predators. It took another 1.5 million years for us to develop the technology to hunt, and only then, after we were the first to kill and were regularly eating the most nutritious parts, did our brains and bodies begin to grow exponentially. It wasn't the left-behind meat that did this; it was the rich, nutritious organs, fat, and other offal, parts that today are discarded, largely considered disgusting, and in some cases even made illegal.
The great irony is that we have taken a gigantic step backward with our modern approach to meat. After our ancestors worked so hard to gain first access to an entire animal, today we are choosing the opposite strategy, eating the less nutritious parts of an animal and leaving the rest. (pp. 62-63)
Offal is essentially what falls off the animal as it is being butchered—that's the source of the word. It can mean different things in different cultures. Only later does it acquire the connotation of "waste product", at least in the United States—in other words, the stuff you don’t eat.
Before that, offal was used in all sorts of products. For example, tripe (the stomach lining) is used in foods like menudo. Blood is used in soup, pudding and sausage like czernina. Pork chitterlings are made from intestines, and pork rinds come from the skin. Sweetbreads are the pancreas, thymus, or other glands of the animal, and are commonly served in kebabs in Iranian street food. Trotters, or the feet of a hoofed animal, are a delicacy in Uganda. Indonesians prepare offal in curries such as gulai otak, or brain curry. Hocks are often used to flavor beans. Lard and tallow are used for cooking and deep frying. Not only fish roe, but fish heads and eyes are commonly found in Chinese soups and in Russian Ukha. And let's not leave out the glory of haggis and kidney pie. Trimalchio's famous feast in Satyricon featured delicacies such as sow's udders and bull's testicles. Meat was always rare and highly prized in antiquity so cultures came up with all sorts of creative ways to prepare it. One of my favorite recent uses comes from this story by the BBC about a chef who uses a pig's bladder to prepare a traditional pasta dish in one of the world's best restaurants:
Cacio e pepe en vessie: A new (old) twist on cacio e pepe (BBC)
How did this change? The story, as with so many things diet-related, has to do with industrialization. Most places used to have regional slaughterhouses back in the day which could butcher animals and make their products available for locals. But when the Transcontinental Railroad opened, beef was shipped from the major ranching centers in the West to central slaughterhouses in a few key locations such as Chicago, Dubuque, Omaha, and Kansas City. Organ meats and offal required colder, more consistent refrigeration conditions than muscle meats, making them less economical to ship long distances. They were thus transformed into "waste" products used by industry instead of valuable food sources for people.
This series of decisions, made solely for economic reasons, has resulted in our modern practice of eating only the flesh from select parts of an animal that has been slaughtered, butchered, packaged, and shipped by someone else. Not only does the average American play no role in any part of the process, most of us don't even know the butcher. (p. 64)
Wander around a food market in many parts of the world and you will see whole animals hanging from racks—not just disembodied parts—but actual animals. Some Asian markets even keep their foods live (although this might not be a good idea in the age of viruses). But this gives people a much better connection to where their food comes from. And it means they have to process and cut up the whole animal themselves and can more fully utilize all of its constituent parts. That’s how most people in agrarian cultures around the world have eaten since forever, and still do in many parts of the world (which are sadly under assault by Westernization).
One solution is, of course, to hunt animals yourself (Schindler grew up hunting with his father in New Jersey). Of course, this option is not available to everyone. Another is to establish a relationship with people who raise animals directly. This allows us to more fully engage with where our meat comes from and to more fully utilize every part of the animal the way our ancestors did:
As modern hunter-gatherers, we can forage wild plants, grow a garden, and source veggies from local markets and growers. When it comes to meat, we can apply the same practices: hunting, trapping, or fishing to obtain animals directly, or getting to know our local butcher or farmer and purchasing our meats there, including organs and other offal...
I realize that some people simply can't bring themselves to kill an animal. And even if they could, why bother with the effort? Our contemporary food system has made this decision easy for them. When we buy a plastic-wrapped piece of pork tenderloin at the grocery store and grill it over a bed of coals, it is a faceless, bloodless, transaction. Most people consider this a perk of our modern food system.
But for me, the opposite is true. I would argue that distancing ourselves from the process—by not knowing how that animals was raised, treated, fed, and killed—is fundamentally unethical and perpetuates a system that treats our food producing animals atrociously and unsafely. Effectively removing ourselves from the things we don't want to be a part of doesn't mean they don't still happen. Rather, it means that they continue without us and, in the absence of our vigilant oversight, terrible situations and practices are enabled. (pp. 65-66)
Today a lot of chefs are increasingly adopting a "nose to tail" approach to cooking. Adventurous chefs are utilizing every part of the animal in dishes. A talented chef can make any part of an animal palatable. Schindler describes his time studying under a chef at a farm in Italy—a country that maintains many of its culinary traditions (and is far healthier than the U.S.A.) He describes how a Calabrian black pig raised on local olives was slaughtered and every part from snout to tail was made into various products: lardo (cured pig fat), bollito (bone broth), 'nduja (a spicy Calabrian sausage spread) as well as variety of traditional dishes: "By the end of the week, all that was left of the two pigs didn't even fit in a medium bowl." (p. 68) Italian cooking in general focuses on the quality of the ingredients rather than just how they are combined (as we tend to do in American cookbooks).
Some of the other pieces of advice he gives are:
Learn how to cut up whole chickens yourself and save the gizzards.
Preserve the fat from animals for rendering.
Keep the bones (along with vegetable scraps) for bone broth.
Freeze the excess.
Bone broth is becoming extremely popular and can be made with commonly-found ingredients (although it takes a bit of time). Rendering lard and tallow takes a bit more effort. The truly adventurous can even learn to cure their own bacon.
Incidentally, I discovered from reading the book that ketchup was once fermented and served in small glass bottles at the turn of the century, making it a fairly healthy condiment. Modern commercial ketchup, by contrast, is not fermented anymore but preserved through adding chemicals and heat and loaded with sweeteners like high-fructose corn syrup5. Commercial mayonnaise, similarly, uses industrial nut and seed oils for the emulsion but can be healthy if prepared with things like avocado oil: "substituting pure avocado oil transforms a food that can cause harm into a food that can nourish." (p. 88). More generally, a lot of recipes that were traditionally cooked in fat or tallow switched over to industrial vegetable nut, or seed oils, which are basically a waste product and therefore cheaper (McDonalds’ french fries are a well-known example of this).
An impression I get from reading all of this is that many of the common foods we eat were once healthy, but once the industrial food system got a hold of them—with it's relentless focus on pushing down prices and profit maximization—they turned into unhealthy junk food, and that’s where we are today. A lot of things we used to make at home became toxic once we started buying them from giant corporations because we were too busy working and making money to do it ourselves.
Another thing that makes me sad is the fact that a lot of "cheap" foods like the fermented root vegetables and offal that Schindler describes used to be the foods of the poor (aka the peasants6), but were apparently extremely healthy and nourishing. Today, by contrast, the poor in the United States (and even much of the middle class) subsist on highly-processed junk food, microwavable dinners, and fast food. Even vegetables are a rarity in some places (i.e. "food deserts"). Let's be honest: the kinds of foods and preparation techniques Schindler talks about are realistically much more available to upper-class "foodies" who are not poor in time or money. The one time I had bone marrow and steak tartare on a menu was at a very high end restaurant. This feels so tragic to me—a reminder that in many ways the poor in industrialized countries are not better off despite all the cheap electronics they can buy.
For length we'll end it there. Next time we'll talk about the great bugbear of Paleo diets: grains and dairy. And we'll find out why eating bugs and dirt isn't so bad after all!
In fact, a culture is intimately connected with the foods it eats. It is one of the most important aspects of any culture, I would argue, and one that is not remarked about often enough (except perhaps by celebrity chefs and Michael Pollan)
One of the reasons why predators are so widespread—they don’t have to evolve biological defenses to the chemical compounds found in native plant species.
Perhaps this is the reason why "meat only" diets work for some people.
Probably the reason why every grifter and his uncle is selling "supplements" to his or her panicked followers. Imagine trying to sell supplement pills to hunter-gatherers!
Stumbled across this great Reddit comment:
"Catsup" (and other spellings) is a broader term than tomato catsup. These other catsups are even more like garum : mushrooms or fish for fermentable protein and onions for sugar. Worcestershire sauce and brown sauce are excellent examples.
From what I can gather, the word comes from Southeast Asia and ultimately a South Chinese word for fish sauce. In the Victorian era there was a boom of entrepreneurs inventing catsup-family sauces using imported ideas and often ingredients.
I haven't yet found a good history of medieval cooking, but both Roman and Norse cuisines had fermented sauces so it stands to reason that Britain has always had them. Apparently mint sauce is an old style, but I hadn't heard of it until today.
Vinegar is super old, a byproduct winemaking. Mustard is also ancient. Mayonnaise was invented by the French and is relatively new.
"The term humble pie derives from medieval times, when it meant a dish made of animal innards served in peasant households." (p. 64)
© 2022
Eat Like a Human - Review - Part 1
Enjoyed the read very much. I recently learned that plants actually don’t have antioxidants in them, and it’s those natural pesticides that stimulate our own bodies to produce antioxidants!
Yeah thanks for this great review, and the second part. I’ll definitely read the book now