Overbreathing | How Common Is Hyperventilation

What is overbreathing?

Overbreathing effects on brain O2 Hyperventilation (or alveolar hyperventilation), since it has the prefix "hyper-", is breathing more air per minute than the medical norm. The values for normal minute ventilation (or respiratory minute volume) at rest for a 70-kg man range from 4-6 L/min for older physiological textbooks and up to 6-9 L/min for some modern textbooks. Obviously, anything that is more 9-10 L/min is defined as "hyperventilation".

Hyperventilation causes hypocapnia (CO2 deficiency) in the alveoli of the lungs and, if there is no ventilation-perfusion mismatch, in the arterial blood and other body cells. In any case (too high or too low arterial CO2 - arterial hypercapnia or hypocapnia), hyperventilation always leads to tissue hypoxia (low oxygen levels in cells).

Official story about overbreathing

Hyperventilation, as nearly all medical sources imply (e.g., Wikipedia, Emedicine.com, and many others), happens rarely, in such cases as anxiety panic, or other more exotic situations. For example, click here. These medical sources cannot even provide the correct definition of hyperventilation or "hyper" + "ventilation". What do we know about exact numbers for ventilation at rest in people with chronic diseases? Do healthy people have normal minute ventilation rates? How common is hyperventilation? What is the real story related to hyperventilation?

Minute ventilation rates (chronic diseases)

Condition Minute
Number of
All references or
click below for abstracts
Normal breathing 6 L/min - Medical textbooks
Healthy Subjects 6-7 L/min >400 Results of 14 studies
Heart disease 15 (+-4) L/min 22 Dimopoulou et al, 2001
Heart disease 16 (+-2) L/min 11 Johnson et al, 2000
Heart disease 12 (+-3) L/min 132 Fanfulla et al, 1998
Heart disease 15 (+-4) L/min 55 Clark et al, 1997
Heart disease 13 (+-4) L/min 15 Banning et al, 1995
Heart disease 15 (+-4) L/min 88 Clark et al, 1995
Heart disease  14 (+-2) L/min 30 Buller et al, 1990
Heart disease 16 (+-6) L/min 20 Elborn et al, 1990
Pulm hypertension 12 (+-2) L/min 11 D'Alonzo et al, 1987
Cancer 12 (+-2) L/min 40 Travers et al, 2008
Diabetes 12-17 L/min 26 Bottini et al, 2003
Diabetes 15 (+-2) L/min 45 Tantucci et al, 2001
Diabetes 12 (+-2) L/min 8 Mancini et al, 1999
Diabetes 10-20 L/min 28 Tantucci et al, 1997
Diabetes 13 (+-2) L/min 20 Tantucci et al, 1996
Asthma 13 (+-2) L/min 16 Chalupa et al, 2004
Asthma 15 L/min 8 Johnson et al, 1995
Asthma 14 (+-6) L/min 39 Bowler et al, 1998
Asthma 13 (+-4) L/min 17 Kassabian et al, 1982
Asthma 12 L/min 101 McFadden, Lyons, 1968
COPD 14 (+-2) L/min 12 Palange et al, 2001
COPD 12 (+-2) L/min 10 Sinderby et al, 2001
COPD 14 L/min 3 Stulbarg et al, 2001
Sleep apnea 15 (+-3) L/min 20 Radwan et al, 2001
Liver cirrhosis 11-18 L/min 24 Epstein et al, 1998
Hyperthyroidism 15 (+-1) L/min 42 Kahaly, 1998
Cystic fibrosis 15 L/min 15 Fauroux et al, 2006
Cystic fibrosis 10 L/min 11 Browning et al, 1990
Cystic fibrosis* 10 L/min 10 Ward et al, 1999
CF and diabetes* 10 L/min 7 Ward et al, 1999
Cystic fibrosis 16 L/min 7 Dodd et al, 2006
Cystic fibrosis 18 L/min 9 McKone et al, 2005
Cystic fibrosis* 13 (+-2) L/min 10 Bell et al, 1996
Cystic fibrosis 11-14 L/min 6 Tepper et al, 1983
Epilepsy 13 L/min 12 Esquivel et al, 1991
CHV 13 (+-2) L/min 134 Han et al, 1997
Panic disorder 12 (+-5) L/min 12 Pain et al, 1991
Bipolar disorder 11 (+-2) L/min 16 MacKinnon et al, 2007
Dystrophia myotonica 16 (+-4) L/min 12 Clague et al, 1994

Note that advanced stages of asthma can lead to lung destruction, ventilation-perfusion mismatch,
and arterial hypercapnia causing further reduction in body oxygen levels.

Sick patients with hyperventilationThis data explains the pathological changes and high prevalence of chronic disorders (or diseases of civilization), due to hyperventilation, in modern population. Since modern people breathe about 2 times more than the medical norm, they usually suffer from low CO2 values in the arterial blood (ventilation-perfusion mismatch is not a very common condition).

Carbon dioxide is a potent dilator of blood vessels (vasodilator) and is crucial for the Bohr effect (O2 transport from red blood cells to tissues). As a result of hyperventilation, modern people experience reduced oxygen levels in the brain, heart, kidneys and all other vital organs. Cell hypoxia causes or favors inflammatory conditions, production of free radicals and suppression of the immune system. Apart from these effects, there are devastating effects of the hyperventilation syndrome on the brain due to hypocapnia or a lack of CO2, which has calming or sedative properties on nerve cells. These and other hyperventilation-related physiological effects promote pathological changes and the advance of chronic health problems, such as cancer, heart disease and diabetes.

Is overbreathing common in ordinary people?

Chronic hyperventilation is very common for ordinary people (or "normal subjects") these days. Their average minute ventilation values are much greater than the normal value, which used to be the norm about 80-100 years ago.

The graph showing hyperventilation in normal modern subjects

Minute ventilation (or respiratory minute volume, or flow of air) is the volume of air which can be inhaled (inhaled minute volume) or exhaled during 1 minute. It is used to measure one's degree of hyperventilation.

Prevalence of overbreathing in the modern population

Based on standard deviations for the above studies related to normal subjects, we can state that over 90% of modern normal subjects breathe more than the medical norms. Therefore, more than 90% of modern normal subjects suffer from chronic hyperventilation. (One can also note that authors of modern yoga books claim that we need to breathe more and expel more CO2.)

This YouTube video (on the right side) provides the definition and info about prevalence of hyperventilation: Hyperventilation.

Technical note. If we consider Wikipedia or some other sources saying 5-8 or 6-8 L/min as a normal range for minute ventilation, then hyper means more than 8 L/min. With numerous studies that found about 12 L/min as an average and bell-shape or Gaussian distribution with standard deviation 2-3 L/min (also common), we know that about 90% will be in the range from 10 to 14 or 9 to 15 L/min. The remaining part will have less than the lower range 9 or 10, or higher than the upper range that 14 or 15 L/min. Therefore, less than 10% of subjects (even less than 5%) are within or less than the norm. We can get the same result even if you assume 6-9 or 5-9 as normal values. These are basics of the theory of probability.

You can leave your feedback and comments below. Thanks.

HTML Comment Box is loading comments...
Back to the Homepage