This is a a common story but a flawed one. Anthropological evidence suggests people were eating starchy tubers for hundreds of thousands of years. Look at hunter-gatherer diets today – especially those of people like the Hadza who still rely completely on the land for sustenance – and you’d be shocked by how many carbs they eat! Besides which, the argument that foods we evolved to eat 200,000 years ago (roughly when anatomically modern humans came onto the scene) are those which are best for us is now faulty. Evolution can happen incredibly rapidly when selective pressure is strong and foods that were foreign 10,000 years ago may actually be highly adaptive for us now. I’d argue that highly processed foods that emerged in the last 200 years are a different story, as we have not had enough time to evolve in response to them. But give us a few more generations, and perhaps it will be a different story.
Slice and dice it how you will, all available evidence indicates that we are eating 10 to 25 times more carbohydrate than we were a couple hundred years ago. And evolution may be fast (which is only a hypothesis, not proven), but it certainly isn’t that fast.
Not only 10-25 more in quantity but earlier generations were eating themfrom pure and unadulterated sources. Truly whole grains (which are no longer consumed by humans despite false advertising claims), root vegetables, nuts, tubers, etc are entirely different animals than today’s processed carbohydrates, high fructose corn syrup, etc
The more we have bastardized carbohydrate sources the more we have made them into glycemic hand grenades.
I don’t think we are eating 10 to 25 times as many carbs as ancestral people. Even Eskimos who eat almost exclusively meat are eating 15 to 20 percent of their calories from carbohydrate – from glycogen in muscle and liver. If, say, the typical American diet includes 300 grams of carbs, then you’re saying the typical person who evolved in Africa, where fatty game are fairly scarce, consumed just 12 grams of carbs a day?? And by the way, humans are literally poisoned if they consistently eat a diet that consists of more than about 200 to 300 grams of protein, so the deficit couldn’t simply be made up by consuming more protein from meat…
I think Sam19 is pointing to a more likely explanation, which is that ancestral populations likely ate a huge amount more fiber and many more nutrients with every gram of usable carbohydrate. This probably meant they were not subjecting themselves to the daily sugar spikes the American diet predisposes people to. I also suspect the lack of fiber modifies gut bacteria in profound ways that alter metabolism, immune function and inflammation.
Our ancestors evolved in different environments. My Chinese husband gets a stomach ache and digestive issues with milk, my northern/southern/eastern European body is fine with milk. Some people come from ancestors who were late to the agricultural revolution. I think I have more of my mom’s Eastern European genes. Genetically (TCF7L2 gene CT snp), I believe I just don’t produce the amount of insulin needed to handle lots of fruit and grains -even amounts that are healthy for a lot of people and don’t produce weight gain in them. Furthermore, I believe that the level of insulin I produce probably doesn’t have anything pathological about it. So far the level of insulin I produce is normal and healthy for me so long as I do a moderate amount of activity throughout the day and mostly eat protein and non-starchy vegetables. If I did more strenuous work, but ate a smaller volume of food, I could probably have starches constitute a relatively bigger portion of my diet.
So we need to talk about different pockets of human evolution- we shouldn’t all be mixed in together.
I think we are. Those figures are based USDA estimates that the average American consumed about 5 lbs of sugar a year at the turn of the 20th century and somewhere between 150 and 200 lbs now.
And that’s only sugar. Doesn’t consider any sort of starch.
I agree that we all have evolved even in the last 50k years or so and I do think genes may alter the beneficial proportion of carbs/fat in different populations. However, we’re all human omnivores – what marks our food, evolutionarily speaking, from other animals is simply the fact that we can thrive on such a varied diet – and yet no human diets found in nature, as far as we know, involve just 12 grams of carbs. I personally think most of us eat too many grams of carbs, but the idea that it’s somehow natural for us to use what is essentially our backup starvation metabolic pathway in order to be healthy is what I don’t agree with.
I also think many on this site are looking for an explanation for what’s behind a disease state – diabetes – and tend to overgeneralize from a specific diet that works for their disease state to claims about what the general population evolved for.
That’s sugar, not carbs – very different. I agree sugar is a huge problem and we may well be eating an order of magnitude or more of it than at the turn of the century. Carbs, by contrast, are in everything except meat. Even a slice of cheese has a gram of carbs in it. It would be difficult if not impossible to craft an ancestral diet that had 12 grams of carbohydrates in it.
Sugar is a carb. If we’re eating thirty or forty times the sugar we used to, then we’re eating many times the carbs we used to. Q.E.D.
Also, I suspect the myriad of people who thrive on a ketogenic diet would view characterizing it as a “backup starvation pathway” as extravagant hyperbole.
The relatively wide incidence of lactose tolerance is a pretty good example of what you’re talking about. Three different mutation events about 10,000 years ago in three disparate geographic communities: now, the species as a whole is slowly but surely moving towards fixation of one or more genes responsible for producing lactase after infancy. If you wind the clock back about 7,500 years, only some Mongolians, eastern Africans, and a handful of people in Northern Europe could drink milk (pleasantly) as an adult…
Evolution is ongoing, relentless, and never-ending. And quite a bit faster than most people realize. I’m an evolutionary ecologist by trade, myself, and the number of questions I get about such things is remarkable.
who said that? i think VLC as Bernstein advocates is an intervention, not a diet for all people.