On Sat, 31 Mar 2001, Norm Skrzypinski wrote:
> OK. I had been under the impression that it was about 5 million years. In
> either case, I admit that it's enough time to allow for some major changes.
> But I really wonder if the natural diet of our closest living relative (97%
> vegetable, 70% carb) can be as different from our best diet as Atkins
> maintains (80-90% animal, < 10% carb).
If you've read Atkins or the Eades then you know that both
recommend this degree of carb restriction as a temporary
therapeutic measure only. Atkins, for example, recommends *two
weeks* of "induction" (20g carbs or less). The Eades recommend
30g or less for agressive treatment of obesity and other
problems, later adding carbs back in. Neither recommend this
level of restriction indefinitely.
In contrast, the Allan and Lutz allowance of 72g/day *is* meant
to be followed indefinitely. On a 2,000 cal. diet, that's about
14%.
> I'm not aware of any evidence that any of our predecessors ever ate a diet
> remotely resembling Atkins' until the last ice age.
I think the point is that the last ice age is precisely the time
when anatomically (and behaviorally) modern humans appeared.
> To illustrate, I'm quite sure that the nearly all-meat diet of the Inuit did
> prevent the transmission of some characteristics (as in 1, above), leaving
> the population better adapted to a high protein and high fat diet. But some
> of the survivors were undoubtedly at or near the limit of their ability to
> metabolize fat and protein, and were in less than optimal health. Also, I
> think it's unlikely that they lost much of their ability to handle carbs (as
> in 2, above) or much further extended their ability to handle protein and
> fat (as in 3, above), during the short (yes, short) time that they've been
> in the arctic.
I have read that the Inuit have lost the sucrase enzyme and have
a difference in delta-5 desaturase response, allowing them to
tolerate high levels of w-3 fats better. I also recall one study
showing them in only trace ketosis even when eating all meat.
This suggests a higher than normal gluconeogenesis output.
These (the latter two, anyway) are rather small "adjustments",
but with significant adaptive benefits.
Todd Moody
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