Vitamin T for Sex
Hot, hot hormones.
Testosterone and the Aging Male
Testosterone levels tend to decline gradually in men, starting in early
middle age. The popular perception, and one trumpeted throughout Sullivan's
piece, is that this decline is a cause of the typical decrease in energy, edge,
and sex drive that often accompanies aging.
But there is simply no scientific data to support a cause-and-effect
relationship between the (slow) decline in testosterone experienced during
normal aging and a negative impact on libido, sexual performance, or level of
energy. Furthermore, even the temporary declines in testosterone experienced by
many men during periods of stress (traffic jams, a poor evaluation by a
superior) typically do not appear to make any long-term difference in their
libido and performance, either.
Behavior Drives Hormones, Not Vice Versa
For argument's sake, let's suppose that for every smidgen of a decline in
testosterone, there was a proportional decline in sexual drive, energy, and
libido, while for every smidgen of a rise, there was an increase. If that were
the case, researchers should be able to select a group of normal, healthy guys
for a study, measure their testosterone levels, and show that the men with the
higher testosterone levels are more libidinous, sexually active, or more
Indeed, some studies have suggested such a correlation. But there turns out
to be a confounding factor: Acting aggressively and having sex both
raise testosterone levels, so the correlation seems due to behavior driving the
hormones, rather than the other way around. This phenomenon has been discussed
in many leading texts on the subject.
When experiments control for those factors -- acting aggressively and having
sex -- the vast majority of studies, whether of humans or animals, show that
individual differences in testosterone levels across the normal range don't
particularly predict individual differences in aggressiveness or sexual
activity. My own study, "Testicular function, social rank, and personality
among wild baboons," published in the journal
Psychoneuroendocrinology (Vol. 16, No. 4, 1991), is among the many to
have found this.