Editor’s note: The “Evolution of Diet” article in the September issue of National Geographic magazine is the fifth installment of an eight-part series. It was incorrectly described as the first installment when the interview was posted online on Aug. 31.
HARI SREENIVASAN: By 2050, the planet will have 2 billion more people on it than it has now. Just how to feed all of those people is a question being explored in the September issue of National Geographic magazine. It’s all part of an eight-month series that begins by looking at the popular Paleo Diet, and what we think our ancestors ate may not actually be the case.
Earlier, I spoke with Ann Gibbons, author of part one, “The Evolution of Diet” and the book, The First Human: The Race to Discover Our Earliest Ancestors.
So, in your reporting you discover that it’s not as much about man the hunter as it is woman the forager. Explain that.
ANN GIBBONS: Yeah, it’s really interesting. So the Paleo diet as we know it today focuses on a lot of meat. It assumes our ancestors were like Neanderthals or cave men going out and hunting and eating big slabs of bloody meat every day.
The reality when you go talk to anthropologists, and this is what I did for the National Geographic article in September. I interviewed a lot of anthropologists and then I went to visit indigenous people and hunter-gatherers and people that are eating traditional diets. The reality is when you see these people and what they eat – they don’t get that much meat. And they don’t get that much meat because hunting is hard work.
While the men go out every day practically and hunt and spend many hours out, even with rifles today, often come back empty-handed. And I saw this for myself with the Chimani foragers in the Amazon, and it was confirmed by anthropologists that I talked to.
And what they rely on are the plants, the fruits, the vegetables that the women and children gather. This is known from studying many traditional people today and also from records in the fossil, records from looking at remnants of food, the plants, the fossils, the molecules that they ate.
HARI SREENIVASAN: And another big difference I suspect between the Paleo Diet and what it wants to do and what it’s doing is that we’re not actually out chasing the deer. We’re not out spending thousands of calories hunting today. I mean, though meat is far more readily accessible, you could actually have that diet, but you wouldn’t be burning those calories.
ANN GIBBONS: Yes, going to the supermarket and buying your grass-fed beef takes a lot less energy, especially if you drive, than going out all day long tracking scrawny antelopes, often the guys in the Hadza hunter-gatherers in Africa in the rainy season, or the dry season, spend days on end and come back with scrawny bits of meat. So much fewer calories and they spend far more energy getting their food.
The real problem for most of our ancestors was getting enough calories. They weren’t that picky about what they ate. As they moved out of Africa, this is our species Homo sapiens in the last hundred thousand years, they adapted to all sorts of terrain and habitats. And the trick was to find the plants and animals that they could eat. You know, plants that weren’t toxic to them.
So, they adapted to all different kinds of environments and ate anything they could eat, but they spent most of their time trying to get that food.
HARI SREENIVASAN: You talk about different hunter-gatherer societies around the planet, from Greenland to Africa to South America, what do they have in common?
ANN GIBBONS: What they have in common is they all want meat, they all crave it. There was one bushman in South Africa who told one of my sources, Alison Brooks at George Washington University, that what his very favorite food was a fatty piece of meat, the type where the fat dripped down his chin. That’s what he was craving. But they don’t get very much of it.
What they all have in common are often starchy carbohydrates. So, the Hadza of Tanzania, those hunter-gatherers dig up tubers, vegetables with lots of carbohydrates. In Papua New Guinea, they get the starchy pith of the Sago Palm. In the Trimany, they were eating plantains, lots and lots of plantains and Cassava – a very bland diet actually. The Mayans have beans, a lot of beans in their diet and corn.
It’s very interesting as you go around and look at these different groups, what they rely on and they almost all have a plant that gives them a lot of calories that’s very starchy.
HARI SREENIVASAN: Now as your article points out, these are really the last remaining peoples that are living this way. Globally, our diets are actually starting to become very similar. Explain that.
ANN GIBBONS: So, the Western diet is spreading rapidly. Whenever a grocery store opens, we begin to see more sugar, salt coming into the diet, and cooking oils. In fact with the Chimmony, what we saw with riverboats bringing salt and sugar in and cooking oil to the people. The father they were from the villages that had those ingredients, the less of that they had. And so those are the staples that are entering all the diets.
When people who have been eating traditional diets, living traditional lifestyles, move into towns or cities and begin to eat the Western diet, they begin to get more sugar, salt, fat, more processed foods. And those give them a lot more calories. You know it’s a lot easier to get calories from Twinkies than it is from vegetables that you have to gather and cook. And so they end up with too many calories and fewer diverse nutrients.
HARI SREENIVASAN: Alright, the article is called “The Evolution of Diet” in this September issue of National Geographic. Ann Gibbons, thanks so much.
ANN GIBBONS: Thank you very much.