Breathing, Hyperventilation, Anxiety, and Hypertension

As you learn how to observe your breathing impartially, you may
notice that even at rest your breathing is faster than the
"average" textbook rate of 12 to 14 times a minute (a rate which
is already faster than it needs to be). In fact, many people,
without knowing it, habitually "hyperventilate," that is, they
take quick, shallow breaths from the top of our chest.

In short, we end up "overbreathing." Overbreathing, like overeating, can
cause many problems. For one thing, it sharply reduces the level
of carbon dioxide in your blood. This reduced level of carbon
dioxide causes the arteries, including the carotid artery going
to the brain, to constrict, thus reducing the flow of blood
throughout the body. When this occurs, no matter how much
oxygen you may breathe into your lungs, your brain and body
will experience a shortage of oxygen. The lack of oxygen
switches on the sympathetic nervous system, your "fight or
flight reflex," which makes you tense, anxious, and irritable.

Such breathing also reduces your ability to think clearly, and
tends to put you at the mercy of obsessive thoughts and images.
Some researchers believe that hyperventilation can actually
magnify our psychological problems and conflicts, and that
chronic hyperventilation is intimately bound up with our
anxieties, apprehensions, and fears. Research has also shown
that unnecessarilly fast breathing can actually raise a person's
blood pressure, and that slowing down your breathing can actually
reduce your blood pressure.

One approach to slowing down your breathing is to learn how to
breathe more fully and naturally, using your diaphragm, belly,
rib cage, and lower back in the breathing process.