Fight or Flight?
by
Mark Sisson
Mark’s Daily Apple
Recently
by Mark Sisson: From
Cancer Back to Health
One of my goals
with this weekly column is to make significant human health issues
easy to understand and discuss. I was pleased that last week’s piece,
the Definitive
Guide to Insulin, Blood Sugar Type 2 Diabetes, garnered
some rave
reviews. The Case
Against Cardio piqued some great conversation and interesting
criticisms (one soul out there in the webosphere took issue with
the fact that I positioned Cardio exclusively from my personal perspective
as a runner rather than authoring a more scholarly article. Well
wasn’t that spot on. It’s called my blog.) My opinions
can’t please everyone, of course, but – based on my experiences
and understanding – I am certain that contributing some insights
on health in light of our (all together now) genetic blueprint is
a worthwhile and timely endeavor.
Now to the
topic at hand. Stress can make you gain
weight, and it contributes to premature
aging. Understanding how stress is related to your overall health
and potentially even longevity is essential to achieving your health
goals. But do not, repeat, do not go and buy yourself a bottle of
Cortislim – just read this quick summary and you’ll know all you
need to know.
Ariel
Amanda Flickr Photo (CC)
The
adrenal glands are not unlike a walnut.
Understanding
Stress
Most folks
are aware that “fight or flight” is the body’s natural response
to stress. When faced with a stressful situation, we either get
aggressive or, in the words of a local surf instructor, we bail.
This choice depends upon our perception of the circumstances and
our corresponding judgment of the odds of success. The “fight or
flight” response is, in terms of energy preservation, tremendously
efficient. And it is very effective at ensuring greater odds of
survival. This makes sense to everyone on a visceral level, but
do you know the physiological mechanisms involved?
The fight or
flight response begins in the brain. Various regions operate in
concert to detect, sense, decode, and respond to a stimulus. Though
there are a few different pathways for a given feeling (like fear)
to travel, it is ultimately the hypothalamus that is responsible
for triggering the fight or flight response. Once the hypothalamus
goes to work, what I call your survival systems, i.e. the “gut”,
kick into gear. They are the nervous system and the adrenal-cortical
system.
Enter
physical symptoms: sweating, heart palpitations, muscles
tensing, hearing sharpening. You are now extraordinarily alert,
but only on the issue at hand: concentration and awareness of anything
else fly out the window. The nervous system has flooded your body
with adrenaline (scientists often refer to this as epinephrine)
and noradrenaline (norepinephrine). Meanwhile, the adrenal-cortical
system (which produces these hormones) becomes activated by way
of the pituitary gland. The pituitary gland secretes a hormone known
as ACTH (adrenocorticotropic hormone…say that three times
fast). ACTH journeys – via the bloodstream – to your adrenal cortex,
where these small organs will pump out as many as 30 different hormones
to address the stressful situation at hand (the adrenals are “fed”
by cholesterol). And your immune system temporarily shuts down so
your body can utilize all its resources to deal with the perceived
threat.
The adrenal
cortex produces cortisol, DHEA, estrogen and testosterone, among
many other hormones. It’s a beautiful system. Unfortunately, what
worked for our old friend Grok does not, I believe, work so well
for us. Simply put, our modern lifestyle subjects us to a potentially
enormous amount of stress on a daily basis that the body has simply
not evolved to handle. To my mind it’s a bit like “deer in the headlights”.
We have a big deer overpopulation problem in my area, and you always
hear comments along the lines of how dumb the deer are around automobiles.
Well, in my opinion they’re not so dumb – in evolutionary terms,
after all, cars are very new on the scene. The deer simply haven’t
adapted the appropriate stress response. Is it so different for
humans?
Listen
to Lew’s recent podcast with Mark Sisson
July 17, 2012
Copyright
© 2012 Mark’s Daily Apple