Tad wrote:

>>Bruce Kleisner wrote:
>>Can anyone explain the rabbit-starvation described by
>>Stefansson and other explorers? Is it just a result of
>>not eating enough Calories? Or "protein toxicity"?
>>
>>
>
>I believe the problem is that the body has an upper limit on the
>amount of protein it can convert to glucose per day. This combined with an
>insufficient amount of fat in rabbits leads to "rabbit starvation."
>
>

It's because we are limited in how much ammonia we can convert to urea.
Ammonia is a by-product of the deamination of protein, which has to
happen before the protein can be utilized.  The interesting thing is
that it seems we have an upper limit to how much protein we can handle,
no matter how much fat or carbohydrate we are eating, because the
protein *must* be deaminated to be utilized.  So it's not that eating
fat or carb makes us able to eat more protein; it's that eating fat or
carb makes us not need or want to eat more protein.  If, for a given
person, the protein ceiling is 300g/day, then if that person eats more
protein that that, he will have problems, even if eating plenty of fat.
But a person eating plenty of fat (or carbs) will not eat more protein
than that.

Todd Moody
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