Dairy

[Joshua Katz]

I know, that's a provocative subject heading.  But then, I have a provocative question.  What's wrong with dairy from an evolutionary perspective?  Yes, the answer seems obvious.  But hear me out.  No other species drinks the milk of another animal, no other species produces enzymes for lactose in adulthood.  Yet, at some point, people started drinking milk, probably out of starvation.  Today, we see that the gene for adult production of lactase is widespread - we consider our kids 'sick' if they are lactose intolerant.  We make cial products for those so 'afflicted.'  So, why did this ability go from almost non-existent to widespread?  Doesn't this suggest that those who could digest milk had an advantage over others?  In turn, doesn't that mean an evolution-based approach to nutrition should see milk (raw milk, at least) and fermented dairy products as ideal foods?

[Toban Wiebe]

Yes, but the same could be said for gluten tolerance. Correct me if I'm mistaken, but aren't Europeans a lot more gluten-tolerant? The way I see it, humans may have evolved recent adaptations to new foods, but these are adapting to tolerate them. It would take a longer period of evolution to adapt to thrive on them.

[Don Matesz]

75% of the world population is lactose intolerant. Tolerance is only
"widespread" among populations with Northern European ancestry
widespread.

So, tolerance is still the less common condition by far.

Also, lactose tolerance is not the only issue. Milk is specifically
formulated to promote growth of infants, hence it contains many growth-
promoting compounds (including hormones) and has an IGF impact that
promotes growth. This is in part why the Masai are so tall. We have
evidence that taller and heavier people have greater risks of cancer
and live shorter lives. Promoting growth is accelerating aging
(increasing cellular reproduction). So although milk might have
indeed saved some Northern Europeans from starvation, tolerance of
lactose doesn't make adults fully adapted to milk consumption.