On Sun, 23 Jan 2000, Kendra and Karen wrote:

> > You can burn body fat when not in ketosis, and you can fail to
> > burn body fat while in ketosis.
>
> Ketone bodies are normal products of fat metabolism and can be oxidized to
> produce energy, right?  So if you are in ketosis how can you not burn body fat?
> Are you saying a person is only burning fat they eat?

That's right.  If sufficient carbs are available, relatively few
ketone bodies are produced when fat is burned, but the fat is
still burned.  Ketone bodies are produced only when fat is burned
*incompletely*, which happens in the absence of glucose.  Then
the ketone bodies themselves are burned as fuel, in a separate
metabolic step.  All of this has *nothing* to do with whether the
fat being burned is stored body fat or dietary fat.  This is why
it is possible to be in ketosis and not lose weight.

This subject is covered very exhaustively in Lyle McDonald's _The
Ketogenic Diet_.

The idea that you have to be in ketosis to be in "fat-burning
mode" is rubbish.  Your cells can and do burn fat when you are
not in ketosis.  If this were not so, then people not in ketosis
would be unable to eat fat without gaining weight, and people not
in ketosis would never be able to lose a pound.  Obviously, this
isn't the way things are.

Todd Moody
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