I think the point is less that the tribes didn’t go vegetarian because this was better for them, and more that if our species subsisted for hundreds of thousands of years on a mixed diet that included meat, odds are our metabolism adapted to that.
Additionally, India might be a relevant case study here, because vegetarianism seems to have been common there for a long time.
The thing is, that likely only happened once civilisation went agricultural, and we know agricultural diet (with a lot less meat for peasants) was a big downgrade and people became significantly more sickly as a result. So it’s a useful case study but not likely to really change the point.
I agree that our metabolism is adapted to eating a mixed diet, but that mostly means that you should not blindly delete animal products from your diet. It is theoretically possible that you can replace animal products with other things, given that we live in a technologically different society. Of course you can say “we do not know what to replace on the micro level”, or make Chesterton’s Fence arguments, but then it is a bit unclear to what kind of diet we should “return”. You can make the adapted-metabolism argument about any selective diet. Maybe we have to eat Offal because our ancestors did, or eat chicken soup because my aunt did that, because these things contain very important things we do not fully understand. Or maybe our ancestors had to eat these things because they were efficient ways to get protein and fat into their bodies, and we consume enough of that already and too much of the bad things we do not fully understand that they also contain. So the adaptation argument alone is not enough.
Well, there are attempts at “paleo diets” though for the most part they seem like unscientific fads. However it’s also true that we’ve been at the agricultural game for long enough that we have adapted to that as well (case in point: lactose tolerance).
Or maybe our ancestors had to eat these things because they were efficient ways to get protein and fat into their bodies, and we consume enough of that already and too much of the bad things we do not fully understand that they also contain.
That doesn’t convince me much, we mostly consume enough (or too much) of that via animal products in the first place. Well, putting aside seed oils, but their entire point is to be a cheap replacement for an animal saturated fat (butter) most of the time. Our diets tend to have “too much” of virtually anything, be it cholesterol from animal products or refined carbs from grains. We just eat too much. The non-adaptive part there is “we were never meant to deal with infinite food at our fingertips and so we never bothered evolving strong defences against that”. Maybe a few centuries of evolution under these conditions would change that.
I think the point is less that the tribes didn’t go vegetarian because this was better for them, and more that if our species subsisted for hundreds of thousands of years on a mixed diet that included meat, odds are our metabolism adapted to that.
The thing is, that likely only happened once civilisation went agricultural, and we know agricultural diet (with a lot less meat for peasants) was a big downgrade and people became significantly more sickly as a result. So it’s a useful case study but not likely to really change the point.
I agree that our metabolism is adapted to eating a mixed diet, but that mostly means that you should not blindly delete animal products from your diet. It is theoretically possible that you can replace animal products with other things, given that we live in a technologically different society. Of course you can say “we do not know what to replace on the micro level”, or make Chesterton’s Fence arguments, but then it is a bit unclear to what kind of diet we should “return”. You can make the adapted-metabolism argument about any selective diet. Maybe we have to eat Offal because our ancestors did, or eat chicken soup because my aunt did that, because these things contain very important things we do not fully understand. Or maybe our ancestors had to eat these things because they were efficient ways to get protein and fat into their bodies, and we consume enough of that already and too much of the bad things we do not fully understand that they also contain. So the adaptation argument alone is not enough.
Well, there are attempts at “paleo diets” though for the most part they seem like unscientific fads. However it’s also true that we’ve been at the agricultural game for long enough that we have adapted to that as well (case in point: lactose tolerance).
That doesn’t convince me much, we mostly consume enough (or too much) of that via animal products in the first place. Well, putting aside seed oils, but their entire point is to be a cheap replacement for an animal saturated fat (butter) most of the time. Our diets tend to have “too much” of virtually anything, be it cholesterol from animal products or refined carbs from grains. We just eat too much. The non-adaptive part there is “we were never meant to deal with infinite food at our fingertips and so we never bothered evolving strong defences against that”. Maybe a few centuries of evolution under these conditions would change that.
Sorry if I was not clear enough but what you write is what I meant as well.