On Mon, 8 Mar 1999, Cynthia wrote:

> It is true that you can be in ketosis without losing weight, the statement
> above only claims that ketosis is a sure sign of fat burning.

True, but it is not a sure sign of burning stored body fat.  If
one is eating enough dietary fat, blood levels of free fatty
acids will rise without stored fat making any appreciable
contribution.  Then when these FFAs are burned incompletely, due
to the absence of sufficient glucose, the result is ketosis.  For
purposes of weight loss, we want *body* fat to be burned, and
ketosis is no guarantee of this.  And of couse it is also true
that fat can be burned when one is not in ketosis.  If this were
not so, it would be impossible to lose body fat on a
non-ketogenic diet.

> Ketones are the byproducts of fat burning, and people who eat high amounts
> of dietary fat are often in 'ketosis' for that reason.

Ketones are the byproducts of *incomplete* fat burning or, more
accurately, two-stage fat burning.  That is, the ketone residues
are themselves used in a separate "burning" process.  A small
amount of ketones are excreted in urine, sweat, etc.

> And it is also true that you can lose water and muscle mass, and thereby
> decrease your weight without burning fat and producing ketones.  But it is
> a bad idea.  You want to burn fat, and when you do you are going to
> produce ketones.  The only debate is, how far into ketosis is it desirable
> to get.

You can burn fat without producing any ketones.  I guess the
desirability of deeper ketosis depends on why one wants to be in
ketosis at all.  I'm in ketosis right now, just as part of the
dietary cycling that I do.  I'm not sure whether there is any
point to it, but I don't think it does any harm.

Todd Moody
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