On Tue, 17 Jul 2001, Alison Whitwood wrote:

> Todd,
>
> Would you elaorate a little on what you said about fructose not filling up
> the glycogen stores (in the liver).
>
> I'm not sure what that means and what the significance is.

Sure.  You have to remember that actual glucose utilization takes
place at about 7.5g/hour.  If you take in more than that, the
excess glucose is stored as glycogen in the liver (and muscles).
Now if you consume a small amount of fructose -- say, 3 or 4
grams -- it will be converted to glucose and it will get used
immediately, so little or none will go to the glycogen reservoir.
If you consume a larger amount, some of it will be burned
directly for energy, along with glucose, but the excess does not
get converted to glycogen; it gets converted to triglyceride,
which is then either burned for energy or store in all the
familiar places.

Starches are polysaccharides that tend to have a lower amount of
fructose, when they are broken down.

A person doing a cyclic lowcarb diet has to "carb up"
periodically, and the purpose of this is to replenish glycogen.
This involves taking in a fairly large amount of carbohydrate in
a short time, so for that purpose the starchier carb is better.
For this purpose a tuber is better than a lot of fruit.

Todd Moody
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