CO2: Health Effects, Uses and Benefits

Brain CO2 health effects: low O2 due to vasoconstriction Contrary to what might be expected from environmental concerns related to global warming, CO2 (carbon dioxide) health effects and benefits for the human body are innumerable. Life originated and had existed on Earth for millennia under conditions of very high CO2 content of the surrounding air. According to published studies, CO2 content was up to about 7-12% in air when the first creatures with lungs were evolving. Therefore, these creatures could experience all CO2 health benefits that are listed below.

Note that very large CO2 concentrations (20% and more) produce adverse effects in humans and pure CO2 is a toxic gas. This web page is focused on typical or physiological CO2 levels in the lungs which range from about 20 to 50 mm Hg or from about 2.7 to 7.5%.

Having a normal level of CO2 in the lungs and arterial blood (40 mm Hg or about 5.3% at sea level) is imperative for normal health. Do modern people have normal CO2 levels? ? When reading the table below note that levels of CO2 in the lungs are inversely proportional to minute ventilation rates, in other words, the more air one breaths the lower the level of alveolar CO2.

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.

CO2 molecule picture Hypocapnia (CO2 deficiency) in the lungs and, in most cases, arterial blood is a normal finding for chronic diseases due to prevalence of chronic hyperventilation among the sick.

Furthermore, as we discovered before, over 90% of modern people (so called "normal subjects") are also hyperventilators (see the link below to the Hyperventilation Table with over 20 medical research studies related to normal subjects). Hence, chronic hypocapnia is very common for modern man.

Main CO2 health effects and uses in the human body

Follow the links for dozens of research references

CO2 vasodilation health benefits - Vasodilation (expansion of arteries and arterioles). As physiological studies found, hypocapnia (low CO2 concentration in the arterial blood) constricts blood vessels and leads to decreased perfusion of all vital organs

- The Bohr effect was first described in 1904 by the Danish physiologist Christian Bohr (father of physicist Niels Bohr). This law can be found in modern medical textbooks on physiology. The Bohr effect states that arterial hypocapnia will cause reduced oxygen release in tissue capillaries.

- Cell Oxygen Levels are controlled by alveolar CO2 and breathing. Hyperventilation, regardless of the arterial CO2 changes, causes alveolar hypocapnia (CO2 deficiency), which leads to cell hypoxia (low cell-oxygen concentrations).

- Oxygen Transport, therefore, depends on breathing and these 2 effects (Vasoconstriction-Vasodilation and the Bohr effect) explain the influence of hypocapnia (low CO2 content in the blood and cells) on circulation and reduced O2 delivery.

- Free Radicals Generation takes place due to anaerobic cell respiration caused by cell hypoxia. Hence, antioxidant defenses of the human body are also regulated by CO2 and breathing, as these medical studies have found.

- Inflammatory Response, as well as chronic inflammation, are also regulated by breathing since hypoxia leads to or intensifies inflammation. Therefore, hyperventilation naturally promotes inflammatory health problems and CO2 and Earthing (electrical grounding the human body) are the key anti-inflammatory agents.

- Nerve Stabilization is due to calmative or sedative effects of carbon dioxide on nervous cells. Lack of CO2 in the brain leads to "spontaneous and asynchronous firing of neurons" (medical quote) "inviting" virtually all mental and psychological abnormalities ranging from panic attacks and seizures to sleeping problems, addictions, depression and schizophrenia.

- Muscle relaxation or relaxation of muscle cells is normal at high CO2 levels, while hypocapnia causes muscular tension, poor posture and, sometimes, aggression and violence.

CO2 bronchodilation health benefit - Bronchodilation - dilation of airways: bronchi and bronchioles are dilated by carbon dioxide, and their constriction occurs due to hypocapnia.

- Blood pH regulation and regulation of other bodily fluids.

- CO2: Lung Damage Healer: Elevated carbon dioxide levels prevents injury and promotes healing of lung tissues.

- CO2: Skin and Tissue Healer.

- Synthesis of Glutamine in the Brain, CO2 fixation, and other chemical reactions: there are many other regulatory and facilitating effects related to uses of carbon dioxide.

- Regularity and Smoothness of Breathing is controlled by CO2. Lack of CO2 leads to "hypocapnic central apnea", which is a popular scientific term used by many doctors and scientists to describe the origins of sleep apnea.

- Hypercapnia (or Hypercarbia): Is it a pathology or a sign of super health?

This myth ("CO2 is a toxic, waste, and poisonous gas") is one of the greatest modern superstitions. Thousands of medical studies have proven that reduced carbon dioxide levels in cells, tissues, organs, and fluids of the human organism cause numerous adverse effects. What are the origins of this myth? In the 1780s, French scientist Antoine-Laurent Lavoisier determined the composition of air. Read more ...

Any medical or physiological textbook, which discusses control or regulation of breathing in the human body, states that breathing is mainly controlled by carbon dioxide concentrations in the brain and arterial blood. Obviously, should CO2 be poisonous, it would be normal to have it as little as possible, but the situation is opposite and the "poison" controls respiration, the fundamental function of the human body...

When chronically hyperventilating, should I experience all these bad effects? The above CO2 deficiency effects take place in all people. However, the degree of these problems and the symptoms (what is felt) are individual ...

Now we can answer the most fundamental questions related to health and genetics. Why and when are bad genes triggered? Why did we have such small rates of chronic diseases only 100 years ago? Genes and diseases: How we react to hyperventilation...

CO2: how evolution of air (disappearance of CO2) promotes chronic disease

This YouTube video "Evolution of Air (Low CO2 Now) Causes Low Body O2 and Chronic Diseases" explains how changes in air composition caused CO2-related health effects, most of all a dramatic shift in consequences of overbreathing. Hyperventilation was beneficial for health long time (it provided more O2 for cells), but not these days.

The web page Evolution of Air from the Section "Causes of Hyperventilation" discusses the same environmental changes in air CO2 content throughout the progress of life on Earth and their effect on health of humans.

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Reference Web Pages: Breathing norms, Medical Graphs and Tables about Breathing Rates (Minute Ventilation) and Body Oxygen in Healthy, Normal and Sick People
Breathing norms: Parameters, graph, and description of the normal breathing pattern
6 breathing myths: 6 myths about breathing and body oxygenation (prevalence: over 90%)
Hyperventilation: Definitions of hyperventilation: their advantages and weak points
Hyperventilation Syndrome: Western scientific evidence about prevalence of CHV (chronic hyperventilation) in patients with various chronic conditions (34 medical studies)
Normal Minute Ventilation: Easy and light breathing (little breathing) in healthy subjects at rest (14 studies)
Hyperventilation Prevalence: Present in over 90% of normal people (24 medical studies)
HV and hypoxia: How and why deep breathing reduces oxygenation of cells and tissues of all vital organs
Body-oxygen test: How to measure your own breathing and body oxygenation (a simple DIY test)
Body oxygen in healthy: CP (body oxygen level) in healthy people (27 medical studies)
Body oxygen in sick: CP (body oxygen level) in sick people (14 medical studies)
Buteyko Table of Health Zones: with clinical description of most common zones
Morning Hyperventilation: Why people feel worse and critically ill people are most likely to die during early morning hours

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