melatonin safety (fwd)

Stephan Anagnostaras stephan at
Thu Oct 12 01:45:28 EST 1995

In article <Pine.3.89.9510110801.D21901-0100000 at>,
rcb1 at LEX.LCCC.EDU (Ron Blue) wrote:

> ---------- Forwarded message ----------
> Date: 10 Oct 1995 18:03:22 -0700
> From: Mark A. McWilliams <mmcwilli at USIBR01.USI.EDU>
> To: ageing at
> Subject: melatonin safety
> To whom it may concern,
>      I was looking for someone to correspond to about questions I had 
> about melatonin.   The questions I had are: How is melatonin supplements  
> produced?  I've been reading various books and articles on melatonin and 
> I've discovered something very shocking.  Melatonin is a by-product of 
> the amino acid tryptophan, right!   The supplement tryptophan has been 
> banned do to bad side effects produced by making synthetic tryptophan.  
> What if they made melatonin out of synthetically produced tryptophan?  
> Would that pose a health hazard?  Just wondering.
> Please send response to:mmcwilli at  

There isn't a good reason to take melatonin and it certainly could pose a
safety hazard. Tryptophan is also the precursor to serotonin (which is
the precursor for melatonin), so this was probably of greater concern
when it was banned.

However, melatonin readily crosses the blood-brain barrier and is
naturally secreted by the pineal body into the circulating bloodstream
in a circadian (and seasonal) fashion.  Adding melatonin would at least
screw up the rhythmicity of this signal (which is a dark signal). This
signal is used to regulate a variety of hormones, including 
prolactin and GnRH (which regulates LH and FSH the primary reproductive
hormones in females).  Moreover, melatonin affects the effectiveness
of estradiol.  Finally, there are melatonin binding sites all over the
brain (even lots of them in the hippocampus) which we have no idea what
they do. So why take melatonin? No good reason, unless you have
nothing better to do.


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