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microwaffles t1_j7ltz67 wrote

Not just ancient. The Netherlands is a great recent example of what happens when dairy consumption is increased (post-WWII I think).

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QTPU t1_j7lvv5w wrote

Dang, a liquid meant to make a large baby beast grow really quickly into a large adult beast makes other beasts grow quickly too!? Daaaaang

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Cleistheknees t1_j7mds8s wrote

Best to contextualize this with the knowledge that the initial transition towards pastoralism and agriculture (ie the Neolithic) brought a major negative impact to overall human skeletal health.

There are hundreds of studies examining this question and generally coming to the same consensus, but here’s a couple more narrative and less jargony ones.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4466732/

https://pubmed.ncbi.nlm.nih.gov/21507735/

The overall takeaway is that agriculture resulted in a severe downturn for human health, but renders out to a net contribution to fitness because of massive increases in ovulation. Women even in extant hunter-gatherer populations experience a total number of ovulatory cycles somewhere around an order of magnetite less than women in agriculture societies, even in what we would today call “developing” conditions, or in older research is sometimes called “third world” or “unindustrialized”.

https://www.jstor.org/stable/4602928

https://www.jstor.org/stable/4602772

https://www.pnas.org/doi/10.1073/pnas.1524031113

From the third citation:

> We examine the effects of sedentarization and cultivation on disease load, mortality, and fertility among Agta foragers. We report increased disease and mortality rates associated with sedentarization alongside an even larger increase in fertility associated with both participation in cultivation and sedentarization. Thus, mothers who transition to agriculture have higher reproductive fitness. We provide the first empirical evidence, to our knowledge, of an adaptive mechanism behind the expansion of agriculture, explaining how we can reconcile the Neolithic increase in morbidity and mortality with the observed demographic expansion.

There is no precise physiological answer as to why, so if someone says they know, they’re either lying or not well-read enough. Agriculture means lots of carbohydrates, and insulin has major effects on sex steroid balancing via its modulation of aromatase, so that is probably a contributor. The massive decrease in population mobility also means a less energy-stressed environment, which is a potent suppressor of ovulation, and also of lactation. Lactation itself also suppresses ovulation, and breastfeeding duration is markedly longer in extant non-agricultural populations, though these groups tend to be somewhat hybridized and not nearly as mobile as their (and our) Paleolithic ancestors, so they should not be taken as a perfect model for those extinct groups.

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jayhl217 t1_j7mlnb1 wrote

Does this mean that vegans will be smaller? What about children who are vegan?

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n3w4cc01_1nt t1_j7o3eoi wrote

it's full of growth hormones for a large mammal. makes sense that it'd work on humans.

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szpaceSZ t1_j7ofhq6 wrote

There is a reason why we do not see huge vegan populations on earth.

Were it more evolutionary for than a mixed consumption, we'd see large groups.

There are not. The closest we get are large religion is vegetarian groups.

Going vegan is clearly evolutionarily unfit.

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NakoL1 t1_j7phtne wrote

This result has probably more to do with protein intake than milk specifically. On average so many children eat bad diets that vegan ones are generally better off

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bigtimephonk t1_j7pq53i wrote

>A recent review of vegan diets in children brings together data from 437 publications with most studies confirming that vegan children have normal growth rates, well within the normal range and a number of benefits that relate to a lower intake of saturated fat, the increased consumption of fibre and phytonutrients and a lower body weight and body fat (8).

https://www.bmj.com/content/375/bmj.n2792/rr

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aupri t1_j7r7ce8 wrote

I mean yeah, if you’re living in prehistoric/ancient times with a scarcity of food then having more sources of food to use is beneficial, but that isn’t really an issue in modern society. People in developed countries are more likely to be overweight than undernourished, because, like many other evolutionary holdovers from our prehistoric past, the urge to eat any and all food you can get your hands on no longer a positive trait in modern society. What was evolutionarily beneficial thousands to millions of years ago is, surprise, not the same as what’s beneficial now

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