The “palaeo” diet bears little resemblance to the real thing
H. isErman Pontzer eating a muffin. Over Zoom it looks delicious. A warm, brown, bland exterior gives way to a fluffy but pale, pale interior. It is a perfect example of all that modern capitalism has to offer in ways of processing food into primal food.
Dr. Pontzer is a professor of evolutionary anthropology and global health. He is an expert on what humans ate thousands of years ago when they were hunter-gatherers. He knows they would not have eaten such things. But he also knows that there are many myths about what people ate before the invention of agriculture. And at a meeting at the Royal Society in London later this month he will explain that their diet was far more diverse than “palaeo” eating advocates think.
For a long time, it was thought that the stone age ancestors of mankind were influenced by meat and avoided carbs. But today’s hunter-gatherers have a very diverse diet, often with lots of plants. Dr. Pontzer has worked closely with the Hadza, a group of them in Tanzania. He has access to four decades of detailed food data on them. The amount of meat they eat depends on what kind of year it is (and it changes from month to month over a year). But in general, the ratio of animals to plants is about 50:50.
Another bias in evaluating actual palaeo foods is the archaeological record. Stone tools and bones that indicate carnivore continue. Evidence for plant consumption is more tenuous. But, says Dr. Pontzer, you will get it. For example, in the “nooks and crannies” of teeth at fossil sites it is possible to discover starchy grains, along with plaque. This suggests that early humans ate plenty of starchy plants.
The best piece of evidence about ancestral human diet, however, is the human body. Human teeth, for example, are not like the teeth of carnivores or the teeth of herbivores, but, instead, like the teeth of omnivores. Not only that, says Dr. Pontzer, but their stomachs are very acidic (and thus destroys pathogens) similar to scavengers like hyenas and buzzards.
If so, there may not be an ideal human diet, and all the official guidelines on what portions of meat, vegetables, grains and dairy are one thing less than what people ‘ think. Dr Pontzer certainly believes so. But this doesn’t quite answer the question why are hunter-gatherers generally thin while an increasing fraction of other people are obese?
A crucial insight came in 2019, when Kevin Hall and his team at the National Institutes of Health, in America, showed in a four-week experiment that people on a diet of processed food (and muffins are an example) eat 500 calories in addition. per day than those on unprepared diets. If modern, highly processed foods are influencing modern humans, what does a hunter-gatherer diet have to say about what a true palaeo diet should consist of?
Here the news is not so good. No healthy food. One Hadza staple is a tuber called the ekwa, a type of “forest carrot”. To make this edible, you have to remove the skin, roast the rest, and then digest it to extract its nutritional value, before discarding the fibrous residue.
Dr Pontzer, who has spent time living and eating with the Hadza, describes the ekwa as “very tasty”. He has also eaten boiled warthog, which he says is “OK” but also tasteless. Berries are completely unlike the stuffy, watery, sugary stuff found in supermarkets. Instead, they are dry, with many seeds inside. The scariest, however, was a weekly zebra.
When the Hadza kill a zebra there is too much to eat in one sitting. Once ingredients such as testicles and other organs are eaten, the rest is cut and hung in the open. It is cooked by being thrown into a fire, but it is definitely not cooked through. “It tastes like ash and it’s bubblegum pink on the inside,” Dr. Pontzer says.
The only foods he would really recommend are local honey and the fruit of the baobab tree. Baobab fruit has a dry, crunchy interior that is a bit like expanded polystyrene, but tangy. It’s not a chocolate chip muffin though. ■
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