Stress - Testosterone
We all joke around about being under stress, but, as you'll see below, it's really
not that funny. There are many definitions of stress, but here I am primarily
talking about the kind of stress that produces elevated cortisol levels. When
you are under stress, your body releases increased levels of adrenaline and
other "fight or flight" hormones and chemicals. The adrenaline
does a certain amount of damage, raising pulse rates and blood pressure
(especially in Type A personalities). But it is the cortisol
that comes shortly after that does the most devastating long term damage.
Many people have trouble understanding what really causes stress and elevated
cortisol levels. Yes, a death in the family, a divorce - those things can
cause stress. But it is really your reaction to these events that produces
what I will call "true stress", i.e. elevated cortisol levels.
Let's start with one counterintuitive example: depression. You would
expect that depression would actually mute or numb any hormonal response, right?
But it's actually quite the opposite. One study found that the cortisol
levels of the depressed individuals was 68% higher than those without
depression.  That same study found
that testosterone, both nighttime and 24-hour, were significantly lower in these
individuals and were negatively correlated with cortisol levels. To put it
directly: the higher the cortisol, the lower the testosterone.
Other studies have verified similar findings. 
So how does stress lower testosterone? Most of the research in this area
was done through Population Council endocrinologist Matthew Hardy and his work
on rats. He and his teams found out how stress lowers your testosterone:
through a tricky little enzyme called 11ßHSD-1.  Your body produces most
of its testosterone in the Leydig Cells of the testes and this enzyme keeps cortisol, the
primary stress hormone, from pushing down your testosterone. It literally
puts the brakes on cortisol from destroying your testosterone. However, in
times of stress, there is simply too much coristol versus 11ßHSD-1
and this leads to a decrease in your testosterone production. Of course,
anything that lowers testosterone is bad for fertility.
This means that stress does not just lower testosterone through adverse
lifestyle changes, but directly through chemical pathways in the gonads. Of
course, stress can also indirectly affect testosterone through "back door" means
as well. For example, it causes us to overeat and a high glycemic load can
will cause testosterone levels to drop within a few hours of a meal.
Likewise, weight gain from the extra "comfort" eating can lead to lowered
baseline testosterone levels in the long term.
The bottom line is that, for the sake of your hormone levels, you've got to take
seriously the goal of minimizing stress in your life. There are other reasons as
well: read my links on Stress and Erectile Dysfunction and
Stress and Your
Brain for more information.
So how can you combat stress? Are there any practical solutions? Please
read my link on
Practical Stress Management Solutions for solutions based on
the latest research.
CAUTION: It looks like a little stress may be a good thing. Researchers have found that mild
stress resulting from an "enriched social, physical and mental environment" ends
up decreasing leptin levels.  Leptin was once considered a "good boy"
hormone, because it decreases appetite and has other positive effects.
However, leptin also causes cancer to thrive and grow and was linked to
increased risk of colon and skin cancer.
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