Hypocapnia (Lowered CO2) in the Blood Leads to Reduced Oxygenation

Published on August 13, 2018

Under clinical conditions, low oxygen and low carbon dioxide generally occur together. Therapeutic increase of carbon dioxide, by inhalation of this gas diluted in air, is often an effective means of improving the oxygenation of the blood and tissues.[1]

Carbon dioxide is one of the most important gases for life. It is healthy and extremely necessary. CO2 is good and without enough of it we get sick. CO2, the waste product of cell metabolism, is not waste at all. Plants thrive on it and our lives depend on it.

Dr. Konstantin Buteyko said, “CO2 is the main source of nutrition for any living matter on Earth. Plants obtain CO2 from the air and provide the main source of nourishment for animals, while both plants and animals are nourishment for us. The great resource of CO2 in the air was formed in pre-historical times when the amount was about 10%.”

Like water it is toxic, when there is too much, but that is as far as one can go in talking about its dangers. Medically speaking, the real problem is when there is not enough—when we do not exercise enough and when we breathe too fast. Improper fast breathing (which is the norm today) causes oxygen deficiency because we are ventilating too much CO2, which contracts the blood vessels and changes the oxygen disassociation curve in a way that suffocates the cell. Hypocapnia (lowered CO2) leads to reduced oxygenation of all vital organs and tissues due to vasoconstriction, and the suppressed Bohr effect.


In 1904, Danish scientist Christian Bohr noticed that hemoglobin binds oxygen more tightly at high pH than it does at low pH. This phenomenon is called the Bohr effect. CO2 and bicarbonate, carbon dioxide’s twin sister, are the vital players in the pH balance in both cells, blood and other bodily fluids meaning CO2 holds the keys to oxygen delivery. If the level of carbon dioxide in the blood is lower than normal, then this leads to difficulties in releasing oxygen from haemoglobin.

Poor oxygenation or hypoxia appears to be a favorable environment
for cancer development whereas good oxygenation favors healthy
tissue growth. Increasing Co2 levels, through the use of sodium
bicarbonate, is good in cancer treatment because bicarbonate drives
up CO2 levels in the blood, which increases oxygenation to the cells.

Most doctors ignore CO2, and this bad because lowered carbon dioxide levels in the blood leads to reduced oxygenation of the cells, which leads to toxic accumulation and increased acidity. This condition has cancer written all over it. If a carbon dioxide deficiency continues for a long time, then it can be responsible for many diseases including accelerated ageing. Little does anyone know that a lack of carbon dioxide is harmful because it is as much of a fundamental component of living matter as oxygen.

As physiological studies found, hypocapnia constricts blood vessels and leads to decreased perfusion of all vital organs. In emergency situations, when these conditions are extreme, the organs and tissues of the body are not receiving an adequate flow of blood.

It is also important to know that hypoxia suppresses the immune system.

“Hypoxia and immunity are highly interdependent. Hypoxia affects molecular and cellular inflammatory processes. Hypoxia activates distinct hypoxia-signaling pathways, including a group of transcription factors known as hypoxia-inducible factors and adenosine signaling. In vitro and animal studies have shown that these pathways are involved in modulation of inflammatory responses. Inflammatory conditions are frequently characterized by tissue hypoxia due to enhanced metabolic demand as well as decreased metabolic substrates resulting from edema, microthrombi, and atelectasis, in turn causing “inflammatory hypoxia.”[2]

Hypoxia supports tumor growth and interferes with effective radiation and chemotherapy. Hypoxia incapacitates several different types of immune effector cells, enhances the activity of immunosuppressive cells and provides new avenues which help “blind” immune cells to the presence of tumor cells. [3] Hypoxia is the enemy of anti-tumor immune response. Oxygenation, on the other hand, would reduce tumors escape from immune surveillance and response.

Several doctors report, “Rapidly growing tumors with poorly formed vasculature have low oxygen levels, and limited oxygen availability results in a hypoxic microenvironment. Patients with high levels of tumor hypoxia have a significantly worse prognosis than patients with low levels. Thus, targeting tumor hypoxia in the treatment of prostate cancer has the potential to improve patient response to treatment and overall survival.”

Hypocapnia (CO2 deficiency) in the lungs and, in most cases, arterial blood is a normal finding in chronic diseases due to prevalence of chronic hyperventilation among the sick. An understanding of the pathogenesis of disease, in which hypocapnia is a constitutive element, is necessary to understand cancer. Hypocapnia is a universal constant behind most disease.

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The Warburg effect (WE), or aerobic glycolysis, triggered by hypoxia, is commonly recognized as a hallmark of cancer and has been extensively studied for potential anti-cancer therapeutics development.[4]

The Bohr Effect

The Bohr effect explains oxygen release in capillaries, why red blood cells unload oxygen in tissues. Bohr stated that at lower pH (more acidic environment, e.g., in tissues), hemoglobin will bind to oxygen with less affinity. The Bohr effect has to do with hemoglobin’s ability to pick up or donate hydrogen ions. As pH rises, hemoglobin loses hydrogen ions from specific amino acids at key sites in its structure, and this causes a subtle change in its structure that enhances its ability to bind oxygen.

When pH falls in the blood, when it becomes slightly more acidic, the reverse happens: hemoglobin picks up hydrogen ions and its affinity for oxygen decreases. The pH of your blood is very tightly buffered thanks to the bicarbonate it contains and to hemoglobin, which can pick up or lose hydrogen ions to counteract changes in pH. Hemoglobin affinity for oxygen is how readily hemoglobin acquires and releases oxygen molecules into the fluid that surrounds it.

Hemoglobin will drop off more oxygen as the concentration of carbon dioxide increases dramatically where tissue respiration is happening rapidly, and oxygen is in need. The opposite is true under low CO2 levels, hemoglobin will drop off less oxygen.

Increasing CO2 concentration drives a decrease in pH, which helps force hemoglobin to dump the oxygen it’s carried from the lungs, so your cells can use it to break down sugars for energy. Decreasing CO2, through faster than normal breathing, has the opposite affect of putting the breaks on oxygen delivery. The pH-mediated change in affinity for oxygen helps hemoglobin act like a shuttle that picks up oxygen in the lungs and deposits it in the tissues where it will be needed.

The dissociation of oxygen is also helped by magnesium because it provides an oxygen adsorption isotherm which is hyperbolic. It also ensures that the oxygen dissociation curves are sigmoidal which maximizes oxygen saturation with the gaseous pressure of oxygen (Murray et al pp. 65-67).

Oxygen dissociation with increased delivery to the tissues is increased by magnesium through elevation of 2,3-bisphosphoglycerate/DPG (Darley, 1979) Magnesium stabilizes the ability of the phorphyrin ring to fluoresce. Free-radical attack of haemoglobin yields ferryl haemoglobin HbFe4+ (D’Agnillo and Alayash, 2001), which is inhibited by magnesium (Rock et al, 1995).

Arterial hypocapnia (CO2 deficiency) causes Tissue Hypoxia

Cell hypoxia is one of the main causes of free radical generation and oxidative stress leading to inflammation, especially in the capillaries. Capillaries are critical determinants of oxygen and nutrient delivery and utilization so inflammation there is telling.

Just so happens that normal arterial levels of CO2 have antioxidant properties. A group of Russian microbiologists discovered that "CO2 at a tension close to that observed in the blood (37.0 mm Hg) and high tensions (60 or 146 mm Hg) is a potent inhibitor of generation of the active oxygen forms (free radicals) by the cells and mitochondria of the human and tissues."[5]

Dr. L.O. Simpson asserts that Fatigue Immune Deficiency Syndrome (CFIDS), results from “insufficient oxygen availability due to impaired capillary blood flow.” Tissue oxygenation is severely disturbed during pathological conditions such as cancer, diabetes, coronary heart disease, stroke, etc., which are associated with decrease in pO2, i.e. ‘hypoxia’.[6] Oxygen delivery is dependent on the metabolic requirements and functional status of each organ. Consequently, in a physiological condition, organ and tissue are characterized by their own unique ‘tissue normoxia’ or ‘physioxia’ status.

Biologist Dr. Ray Peat tells us that, “Breathing pure oxygen lowers the oxygen content of tissues; breathing rarefied air, or air with carbon dioxide, oxygenates and energizes the tissues; if this seems upside down, it’s because medical physiology has been taught upside down. And respiratory physiology holds the key to the special functions of all the organs, and too many of their basic pathological changes.”[7]

People who live at very high altitudes live significantly longer;
they have a lower incidence of cancer (Weinberg, et al., 1987)
and heart disease (Mortimer, et al., 1977), and other
degenerative conditions, than people who live near sea level

Every cell in our body can recognize and respond to changes in the availability of oxygen. The best example of this is when we climb to high altitudes where the air contains less oxygen. The cells recognize the decrease in oxygen via the bloodstream and are able to react, using the ‘hypoxic response,’ to produce a protein called EPO (erythropoietin). This protein in turn stimulates the body to produce more red blood cells to absorb as much of the reduced levels of oxygen as possible.[8]


Carbon dioxide like air, water and oxygen is essential for life, health and specifically, it holds the key to resolving asthma, cancer and many other chronic diseases. Carbon dioxide is an essential constituent of tissue fluids and as such should be maintained at an optimum level in the blood. The gas therefore is needed to supplement various anaesthetic and oxygenation mixtures for use under special conditions such as cardio-pulmonary by-pass surgery and the management of renal dialysis.

Dr. Ray Peat says, “Breathing too much oxygen displaces too much carbon dioxide, provoking an increase in lactic acid; too much lactate displaces both oxygen and carbon dioxide. Lactate itself tends to suppress respiration. Oxygen toxicity and hyperventilation create a systemic deficiency of carbon dioxide. It is this carbon dioxide deficiency that makes breathing more difficult in pure oxygen, that impairs the heart’s ability to work, and that increases the resistance of blood vessels, impairing circulation and oxygen delivery to tissues. In conditions that permit greater carbon dioxide retention, circulation is improved, and the heart works more effectively. Carbon dioxide inhibits the production of lactic acid, and lactic acid lowers carbon dioxide’s concentration in a variety of ways.”[9]

Summarizing, low cell oxygen levels due to 2 effects, constriction of arteries and arterioles (since CO2 is a most potent vasodilator) and the suppressed Bohr effect. There are actually many reasons for low oxygen, and even red blood cells have been reported to shrink and become stiffer under hypoxic conditions. [10] (See chapter ‘Multiple Causes of Low Oxygen Conditions’ this Thursday)

[1] Henderson, Y. Carbon Dioxide. Article in Encyclopedia of Medicine. 1940

[2] Immunologic Consequences of Hypoxia during Critical Illness. Harmke D. Kiers, M.D.; Gert-Jan Scheffer, M.D., Ph.D.; Johannes G. van der Hoeven, M.D., Ph.D.; Holger K. Eltzschig, M.D., Ph.D.; Peter Pickkers, M.D., Ph.D.


[3] Int J Hyperthermia. 2010; 26(3): 232–246. Hypoxia-Driven Immunosuppression: A new reason to use thermal therapy in the treatment of cancer?

[4] Front. Endocrinol., 23 October 2017 | https://doi.org/10.3389/fendo.2017.00279. The Emerging Facets of Non-Cancerous Warburg Effect

[6] J Cell Mol Med. 2011 Jun; 15(6): 1239–1253. Why is the partial oxygen pressure of human tissues a crucial parameter? Small molecules and hypoxia

[7] ibid

[8]Acute normobaric hypoxia stimulates erythropoietin release.

Mackenzie RW1, Watt PW, Maxwell NS.; High Alt Med Biol.; 2008 Spring; 9(1):28-37. doi: 10.1089/ham.2008.1043; http://www.ncbi.nlm.nih.gov/pubmed/18331218

[9] http://raypeat.com/articles/aging/altitude-mortality.shtml

[10] Int J Hyperthermia. 2010; 26(3): 232–246. Hypoxia-Driven Immunosuppression: A new reason to use thermal therapy in the treatment of cancer?

Dr. Mark Sircus AC., OMD, DM (P)

Professor of Natural Oncology, Da Vinci Institute of Holistic Medicine
Doctor of Oriental and Pastoral Medicine
Founder of Natural Allopathic Medicine

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