HELP: re the cholesterol > serotonin question

Syd Baumel ravel at cycor.ca
Thu Dec 19 14:28:17 EST 1996


I need some expert information/opinion for a book I'm writing on the
neurotransmitter serotonin.  (Please forgive the generic quality of this message
because I'm crossposting to several relevant, but very different newsgroups.)

As many readers here may know, serotonin has been implicated in the perplexing
fact that lowering blood cholesterol, while it reduces heart attacks, usually is
associated with a comparable increase in mortality due to other causes, notably
suicide, homicide, and accidental death.  The theory is that, because
cholesterol apparently facilitates serotonin activity in the brain, lowering
cholesterol tends to provoke such well-known symptoms of low serotonin as
depression, suicide, violence/aggression, and poor impulse control (recklesness,
etc.).

Needless to say, this is a hard pill to swallow for those (like myself) who
would rather continue to believe in the virtue of comparatively low cholesterol
levels and dietary intake.  A couple of potentially "saving explanations" have
occured to me, but I don't have time as I research my book to "fact check"
them on my own, so I'm asking for input from those who already may have some
answers.

The first hypothesis relates to the fact that megadoses of vitamin B3 in the
form of niacin have, in at least one or two long-term studies (precise numbers,
anyone?), lowered cholesterol significantly without increasing mortality due to
noncardiac causes -- in fact, they've decreased overall mortality, just as a
good "drug" should do.  For me, this begs two questions:

Could niacin's benign effect have anything to do with the fact that large doses
would spare a certain amount of serotonin's precursor, tryptophan, from being
converted to niacin, thus indirectly raising or preserving the brain's serotonin
content?

Megadoses of niacin not only lower LDL cholesterol, but they also are superior
to all (most?) cholesterol-lowering drugs in their ability to lower
triglycerides, and unlike all (most?) of these drugs they also raise, rather
than lower, the "good" HDL cholesterol.  This makes me wonder if the association
between lower cholesterol and signs of lowered serotonin might be due
specifically to the HDL-lowering effect of most cholesterol-lowering regimes
and/or if relatively high HDL offsets the potential pitfalls of lowering LDL.
(I.e. Is it the HDL component -- not LDL or VLDL -- that is responsible for
boosting serotonin?) This also makes me think of another related concern I have:
Low cholesterol is the norm in many non-Western populations which not only
appear to be healthier than Western populations as far as degenerative diseases
are concerned, but which, as far as I know, do not seem to be suffering the
adverse consequences of lowered serotonin.  Am I right in suspecting that these
populations also tend to have high levels of HDL.  Is there a connection?

Your comments, here or via e-mail, will be greatly appreciated.

Syd

Syd Baumel
author of Dealing With Depression Naturally
Keats Publishing, Inc.  1-800-858-7014  http://www.keats.com




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