On Wed, 12 Aug 1998, Ilya wrote:

> Todd Moody wrote:
> > The amount of fat excreted as ketones is trivial.
> Do you have any numbers on this? I'd be interested in seeing them.

Not handy.  This topic was explored in detail on one of the
lowcarb lists a year or so ago, as I recall.

> My energy needs when not on a low carb diet are in the 2500 Kcal/day
> range (I am a 5'6" male, 34 yo). I have lost weight easily (and
> without exercise) on a low carb diet while eating well in excess
> of 3500 calories per day (often around or higher than 5000) for days
> on end. I was NOT grossly overweight when doing so. From lowcarb
> exercise list I am aware of at least one other person with similar
> experience.

That's a very wide range of variation, but very plausible to me.

> > Is it "impossible to
> > store fat in ketosis because there is no insulin available to
> > facilitate its storage"?  No.  Protein stimulates insulin
> > release.
> This is rather small compared to what you get when eating carbs.
> Couple that with slowed down digestion due to all the fat in the
> diet and you are talking about a very small amount of insulin.

As I understand it, there is always a baseline insulin output,
regardless of diet, because insulin is involved in controlling
many cellular functions.  According to the Eades, the insulin
response to protein is about 40% of the response to carbs.  It's
less, but certainly not negligible.  This slows the rate at which
excess fat is stored, but doesn't halt it.

> >  Ketones stimulate insulin release.
> Only true once their concentration reaches sufficiently high levels.
> Which means you are already burning fat in overdrive. At that point
> insulin is released to stop/slow down further fat burning, not to
> store fat. You will not be storing fat under such conditions.

Burning fat does not imply reducing body fat, if fat intake
exceeds what you are burning.  You *will* be storing fat if there
is more fat coming in than can be burned.

> > Even the Eades, of _Protein Power_, concede that calories count.  The
> > body's energy needs are not fixed, but they are not infinitely
> > elastic either.
> True, but neither are eating habits of people on a keto diet. The
> combination of not burning fat completely (thus ketones in urine
> and breath) and a reduced ability of the body to store fat result
> in fat loss even when eating over nominal requirements. It is
> true that if you eat enough you will not LOOSE weight, it is also
> true that a great many people will not GAIN any on a keto diet
> even when eating much beyond their normal caloric needs.

Most of the fat *is* burned completely, but in two stages instead
of one.  The first step produces ketones, but then the ketones
are also burned.  I don't doubt that keto raises the "ceiling" of
how many calories can be ingested without weight gain; I'm pretty
sure that it does.  The point is only that there is still a
ceiling.  And the related point is that ketosis does not
guarantee weight loss.  As you state above, if you eat enough you
will not lose weight, despite being in ketosis.

Todd Moody
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