Todd Moody wrote:

>Well, if the stuff I have read is sound, the insulin response to
>protein is a curve that is relatively flat for portions up to
>about 35g, but beyond that rises sharply.  At the flat part of
>the curve, the insulin response to protein is about 40% that of
>carbs.  Interestingly, this dovetails pretty well with the claim,
>in physiology textbooks, that 580f protein is burned as fuel
>anyway.  There is some variation according to the amino acid
>content of the protein, however.

The things you mention fit nicely into the puzzle of facts
as I understood them, regarding protein usage.
Amino acids not needed for direct usage to build up
enzymes or other parts of the body (hair, nails, growth)
are downgraded to glucose (plus waste) and ready for energetic use.
These unneeded amino acids are the "wrong" ones , that come from the
unideal amino acid composition (of most proteins)
plus the whole proteins that exceed the human capacity to
be stored and used as such.
You mention 35g protein after which  the conversion rate goes up.
I guess that's per meal and not per day.
For how many meals would that work? 2 or 5?
Somehow the amino acid storages of the human will fill up
before the burning mode begins, and they can fill up only if empty.
The size of this amino acid storage in an average human (70kg)
is 55g of amino acids. This fits to your 35g protein per meal
if you assume that about 5010000061074f the amino acids are usable
and about 3 meals per day. *if* this a.a.storage is designed
to last for exactely one day (i'd expect more).

You seem to see the insulin response as something negative.
Insulin is the body's signal *use* glucose.
It can be used in two ways
1. restructure it into storage for later use
   (glycogen for short term, and body fat for long term)
2. direct use by the body cells
   (muscles need that signal, brain needs it not since it is
   essential for it anyway)
I've an idea how it could be, that most blood sugar ends up
in path 1, therefore creating the dreaded fat gain:

Body cells, in order to *burn* the glucose (path 2)
must have (besides insulin)
several enzymes to accomplish the burning event.
One of these is thiamin - Vitamin B1 again.
If carbs are available only with unsufficient amounts of thiamin,
(as in SAD standard and even in some fruit).
Then path 2 will be blocked, and all the glucose will be
built to fat.

In this way *any* glucose source (starch, sugar and protein)
will result in fat gain.
Besides unsatisfied hunger for fuel energy by the body cells.

If neanderthin converts most of the energy input to fat -
fat breakdown doesn't seem to need thiamin - fine: it can be used..
Paleonutrition demands  unprocessed food for carbs:
fine: it can be used too, because containing enough of thiamin
(maybe except some extremely sweet cultivated fruit)
Most meats contain a reasonable vitamin-b1-amount
way below a possibility to aquire RDA amounts but maybe enough
to burn the (little) glucose fuel emerging from protein breakdown.

That leaves to understand for me:
Why do protein carbs too cause weight gain (with , Todd)
Why can people avoiding conventional carb-foods gain weight?
Can thiamin supplementation lessen fat gain (as you suspected)?

Maybe: the energy deprivation from glucose hungry cell
may cause some long term lasting eating habits.
Or:
Maybe there are some more stuffs necessary for the burning
process than just thiamin.
Is there any doctor or physiologist among us who can
inform us about this detail from the Krebs-cycle?

regards
Amadeus

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