Seasonal Depression: Two Peaks: Winter and Summer: Low DHEA

Copyright 2004, James Michael Howard, Fayetteville, Arkansas, U.S.A.

In 1985, I first suggested depression may result from low dehydroepiandrosterone
(DHEA).  This has since been supported.  I have just recently had the need to
explain why infection rates increase in winter and in summer.  I also first
suggested that HIV infection is due to low DHEA in 1985.  Subsequently, I
decided that low DHEA should also result in increased infection rates from
viruses and other agents so I examined the possibility of low DHEA in winter.  I
found a direct connection (below).  A new report that "Women [are] more
susceptible to HPV [human papilloma virus] during summer" points out that this
is not due to increased sexual activity but may be due to sunlight (March 30,
2004).  (HPV is a sexually transmitted infection.)  Dr. William Hrushesky
reported this finding at the American Association for Cancer Research meeting in
Orlando.  I was also able to explain how this occurs as low DHEA (below).

The same mechanism, low DHEA, that results in two peaks of infection rates also
may explain two peaks of depression.  Now, it is known that testosterone
decreases the effectiveness of the immune system while DHEA increases the
effectiveness of the immune system.  Testosterone in people increases in the
autumn and winter.  DHEA sulfate is also higher in the autumn and spring.  I
suggest the reason is that increased testosterone of autumn and winter reduces
production of DHEA from DHEA sulfate.  This may be the reason that infections,
such as influenza, increase in the winter and why depression is higher in the
winter.

It is my hypothesis that the pineal hormone, melatonin, interacts with DHEA to
control, what I call, the "melatonin - DHEA cycle."  Also, in 1985, I suggested
this cycle controls sleep so it is involved in circadian rhythms.  It is known
that DHEA is involved in the control of melatonin production and melatonin is
involved in DHEA production.  Melatonin production decreases during times of
strong sunlight.  If melatonin production is reduced by strong sunlight which
occurs in the summer, then DHEA will be reduced.  If DHEA is reduced, I suggest
this will precipitate depression in people vulnerable to depression.

A single mechanism may be involved in all depression: low DHEA.  The same
mechanism may affect people when DHEA is seasonally low, such as winter and
summer.

James Michael Howard
www.anthropogeny.com