On Thu, 21 Mar 2002, Katrina wrote:

>  > Ketosis is caused by
>  >the metabolism of dietary fat when carbohydrate is unavailable or during
>  >starvation. Ketosis elevates blood levels of two ketone bodies
>  >(D-beta-hydroxybutyrate and acetoacetate) which provide the brain with a
>  >non-glucose substrate, thereby sparing muscle from metabolic destruction
>  >for glucose synthesis -- remember, except for ketones, the brain can only
>  >use glucose as a fuel.
>
> This seems to confirm my hypothesis that the brain does indeed require a
> substantial amount of glucose during periods of high work load (i.e., every
> day, except weekends).

That's correct.  Brain PET scans show the increased activity.

> Can I ask if there is anybody here who has a mentally exhausting job, and
> is able to stick to a strict lo-carb paleo diet (i.e., only one piece of
> fruit and no complex carbs)?

Anecdotal confirmation: The most mentally exhausting part of my
job is grading exams and papers.  It is at these times that my
craving for carbohydrate is greatest.

Todd Moody
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