Lower carbon dioxide within the blood causes a constriction of the carotid artery, the main blood vessel going to the brain. The extent of constriction depends on genetic predisposition but has been estimated by Gibbs to be as much as 50% for those with anxiety and panic attacks. .
This finding is also supported by Ball & Shekhar . Other researchers, including Balestrino and Somjen  and Huttunen et al. , have demonstrated that CO2 reduces cortical excitability. Cited in Normal Breathing: the key to vital health, “breathing too much makes the human brain abnormally excited due to reduced CO2 concentrations. As a result, the brain gets literally out of control due to appearance of spontaneous and asynchronous ‘self-generated’ thoughts.” Balestrino and Somjen in their summary directly claimed that, “The brain, by regulating breathing, controls its own excitability” .
Dr Robert Fried, professor of psychology, states that “the first stage of chronic graded hypoxia (insufficient oxygen), which has repeatedly been shown in the case of chronic hyperventilation, is depression of mood and activity" . Cardiologist Claude Lum comments that “Hyperventilation presents a collection of bizarre and often apparently unrelated symptoms, which may affect any part of the body, and any organ or any system” . He further labels hyperventilation syndrome as the fat file syndrome, noting that patients go from doctor to doctor in an attempt to get help for their symptoms. However, because chronic hyperventilation is overlooked in most instances, the patient might be told after a series of tests that there is nothing wrong with him or her, thus increasing the size of the patients’ file and further adding to his or her anxiety.
In the late Professor Buteyko’s words, “Exhaling Carbon Dioxide from the organism brings about spasms in bronchi, vessels and intestines, etc. This reduces oxygen supply, leading to oxygen deficiency, making one’s breath heavier, thus completing the vicious circle.”
Stress, anxiety and anger causes overbreathing
According to the famous physiologist Walter Cannon, stress activates the fight or flight response. Meeting deadlines, financial pressures, time urgency, marital issues, the pressure of rearing children and wanting to do well in our work, as well as many other factors, add to stress levels.
Stress ensures survival of the species
Stress is a natural reaction that we have developed throughout our evolution to ensure the survival of our species. Invariably, stress is our body undergoing chemical change in response to environmental conditions. Thousands of years ago, our main threat was from wild animals. When confronted, we had two options to deal with it. The first was that we fought the animal. The second was that we ran away from it as fast as we could. As our bodies were required to perform intense physical activity, our physiology changed in the following ways:
• Our breathing volume increases
• Our heart rate increases
• Adrenaline is pumped into our system
• Our pupils dilate
• Blood is diverted from our internal organs to our arms and legs
• Diarrhoea may occur (lightens our weight before flight)
• Our blood coagulates in case of injury
However, today our society and environment have changed at a far greater pace than what our bodies can adjust to. We respond to the stresses of today with the same reaction as we had thousands of years ago. We are in a traffic jam rushing to get to a meeting. The fight or flight response is activated but there is no need for it. Our heart rate increases, blood is diverted to our skeletal muscles, our breathing increases — we are primed for physical activity yet we are sitting still. The result is that we are running on the inside and sitting on the outside. The heavy breathing arising from the fight or flight response results in a washing out of carbon dioxide from the lungs. This causes a narrowing of blood vessels, thus reducing blood flow to the brain.
In addition, the release of oxygen from blood cells is less; the result of an inhibited Bohr Effect. This in turn increases self-generated, and more random, thoughts. With uncontrolled thought activity, we feel unable to cope with our everyday activities, further increasing our stress. A vicious circle has commenced, with stress increasing our breathing and this in turn increasing our stress. Addressing chronic hyperventilation with the Buteyko Method improves oxygenation of the brain and provides the sufferer with a greater control of their breathing and understanding of the relationship between stress, breathing and vice versa.
For the many years, Patrick McKeown has taught the Buteyko Method to thousands of children and adults. His book Anxiety Free: stop worrying and quieten your mind combines the Buteyko Method and mindfulness for anxiety, racing mind and brain fog.
1. DM Gibbs, 'Hyperventilation induced cerebral ischemia in panic disorder and effects of nimodipine', American journal of Psychiatry (1992), vol 149, pp 1589-1591.
2. Ball & A Shekhar, 'Basilar artery response to hyperventilation in panic disorder', American journal of Psychiatry (1997), vol 154 (11), pp 1603-1604.
3. M Balestrino & GG Somjen, 'Concentration of carbon dioxide, interstitial pH and synaptic transmission in hippocampal formation of the rat', J Physiol (1988), vol 396, pp 247-266.
4. J Huttunen, H Tolvanen, E Heinonen, J Voipio, H Wikstrom, RJ Ilmoniemi, R Hari, K Kaila, 'Effects of voluntary hyperventilation on cortical sensory responses. Electroencephalographic and Magnetoencephalographic studies', Exp Brain Res (1999), vol 125 (3), pp 248-254.
5. Artour Rakhimov Ph.D, Normal Breathing - The key to vital health.
6. Robert Fried, The Hyperventilation Syndrome.
7. LC Lum, 'Hyperventilation: the tip and the iceberg', Journal of Psychosomatic Research, (1975), vol. 19 (5-6), pp 375 - 383.