On Fri, 27 Oct 2000 14:58:27 +0100, Andy <[log in to unmask]>
wrote:

>> Because protein amounts above approximately 0.4g/kg bodyweight are
>> burnt anyway (which unavoidable to a certain extent, because of the
un-ideal
>> composition of all real existing proteins).
>
>This is 40g for a 100 kg man. Is this per meal or per day?
>

This is per day and is much lower as some protein popes consider to be
good
( 1 or even 2 g per kg and day).
But the low amount is the amount of only the ideal amino acids.
Real proteins have an unideal composition and the amount to be eaten
must
therefore be around double of this, at least.

There has been criticism (from Todd) about the way these numbers have
been
determined (nitrogen balance tests). They work by giving a high supply
of a
given protein, which is slowly reduced until the point is reached when
nitrogen input and output is equal (the necessary amount determines
the
quality of the protein).
Possibly the body could economize when the supply is going lower.

Furthermore for low-carbers or people eating few carbohydrates, all or
much
carbohydrate fuel of the body (could have a minimum around 300-700
kcal)
has to come from degraded protein. This increases protein requirements
greately.

There's also the aspect, that paleolithic diets were probaly high in
protein
(regardless if they were high in meat or not), because fruit
availability
decreased. This speacks for a diet higher in protein as essentially
necessary (because it was also higher in paleo-timeframes).

Pre-paleolithical diets are rich in fruit which is high in
carbohydrates
while around RDA in protein.

regards

Amadeus