--- In FairfieldLife@yahoogroups.com, "shempmcgurk" <shempmcg...@...> wrote: > > --- In FairfieldLife@yahoogroups.com, "authfriend" <jstein@> wrote: > > > > --- In FairfieldLife@yahoogroups.com, "shempmcgurk" <shempmcgurk@> > > wrote: > > <snip> > > > I'm not a biologist or geneticist but I think that > > > 10,000 years is more than enough time for a species > > > to select genetic traits. So I think you strengthen > > > my point by reminding us that it's "only" been > > > 10,000 years that dairy has been a part of the human > > > diet. > > > > In fact, in populations that continued to drink milk > > beyond weaning age, there *has* been genetic > > adaptation, at least with regard to lactose intolerance. > > But dairy has not been part of the human diet universally > > by any means since 10,000 years ago, so the gene that > > turns off the ability to digest lactose after weaning > > persists, in widely varying percentages among groups > > with common ancestry (Ashkenazi Jews and others of > > Northern European ancestry, for example, have a very > > low percentage of lactose intolerance, whereas African > > Americans have a very high percentage). > > I wonder what it is amongst the Japanese who, I understand, > had a non-existant dairy-based diet until recently (it was > largely fish and rice based).
Lactose intolerance among the Japanese has been decreasing in recent years.
