A historical chronology of scientific discoveries on breathing, oxygen, carbon-dioxide, health and fitness.
By Drs. Eduard Reuvers
In this first period of development of the science of breathing it was discovered that combustion in a fire has many similarities to combustion in living beings. It started with the discovery of carbon dioxide and oxygen gases. It was then discovered that fires and living beings both consume oxygen and produce carbon dioxide and that the concentration of carbon-dioxide and oxygen in the air determines life and death of living beings and plant-life.
1756: Discovery of carbon dioxide (CO2) by Joseph Black (link).
1774: Discovery of oxygen (O2) by Carl Wilhelm Scheele, Joseph Priestley and Antoine Lavoisier (link).
1775: Joseph Priestley discovers that animals' breathing lowers oxygen and increases carbon-dioxide levels of air while plants increase the oxygen content of air and lower the carbon-dioxide content of air (link).
1777: Discovery of the principle of combustion by Antoine Lavoisier (link). He discovers what happens in a fire: oxygen feeds the fire and carbon-dioxide is released into the air when a fire burns.
1778: Discovery of photosynthesis by Jan Ingenhousz: Plants lower carbon-dioxide levels and increase oxygen levels only when they receive light (link).
1783: Discovery of further details on photosynthesis by Jean Senebier: Plants use carbon-dioxide as a nutriment and carbon dioxide is converted into oxygen in the green parts of the leaves (link).
In the second period of development of the science of breathing it was discovered that although combustion as in a fire takes place in the cells of living beings, metabolism in living beings is much more complicated because it depends on many intricate subsystems. Scientists discovered how oxygen and carbon-dioxide are transported in the blood and how the body automatically regulates its own breathing process.
1803: Lazarro Spallanzani discovers that metabolism (burning oxygen to generate energy) actually takes place in cells (tissue). The blood carries oxygen from the lungs to cells and carries carbon-dioxide back from the cells to the lungs (link). It took another 50+ years for his discovery to be accepted by the wider scientific community, leading to a long delay in further discoveries.
1864: Felix Hoppe-Seyler discovers how the blood transports oxygen: Oxygen binds loosely to hemoglobin in the blood, forming oxyhemoglobin (hemoglobin with oxygen attached) (link).
1864: Eduard F.W. Pflüger discovers that in the presence of hemoglobin, carbon dioxide leaves the blood plasma more easily. This proves that hemoglobin plays a part in the transport of carbon-dioxide by the blood (link).
1868: Josef Breuer and Ewald Hering discover the Hering–Breuer reflex: The automatic nervous response given to the diaphragm by the breathing center in the medulla oblongata to start a new inhalation at the end of each exhalation and to start a new exhalation at the end of each inhalation (link).
1885: Friedrich Miescher discovered that the carbon dioxide levels of the blood (rather than the oxygen levels) determine the chemically-based automatic breathing response by the breathing center in the medulla oblongata. This is the way chemical subconscious breathing control takes place (link). Friedrich Miescher's conclusion was: "Over the oxygen supply of the body, carbon dioxide spreads its protecting wings".
1904: Christian Bohr discovers the Bohr effect: The strength of hemoglobin's chemical bond with oxygen depends on the carbon dioxide content and acidity of the blood. Because the acidity of the blood is highly dependent on its carbon dioxide level, in practice this means that when the blood contains more carbon-dioxide, oxygen leaves the blood more easily and cells receive more oxygen (Bohr et al 1904).
1905: Frederick F. Blackman discovers that a higher carbon-dioxide content in the air accelerates photosynthesis and makes plants grow bigger and faster (Frederick F. Blackman 1905).
1905 - 1909: Haldane, Priestley and Douglas show that breathing (minute volume) is quite unaffected by moderate changes in the content of oxygen in the air or the blood while it automatically and closely follows any changes in the level of carbon-dioxide (Haldane & Priestley 1905, Haldane & Douglas 1909).
1906: Nathan Zuntz discovers that most CO2 is stored in the blood plasma as bicarbonate (HCO3) and that hemoglobin assists in the conversion of carbon dioxide into bicarbonate. He also made the discovery that the CO2 content of the blood is directly determined by how many liters of air we breathe in and out per minute (minute breathing volume) (biography of Nathan Zuntz).
1914: Haldane discovers the Haldane effect: When the blood contains more oxygen, it's easier for carbon dioxide to leave the blood. This effect mirrors the Bohr effect (1904 above) and helps the blood offload more carbon-dioxide to the lungs (Haldane et al 1914).
In this third period of development of the science of breathing, oxygen and carbon-dioxide started to be used for the treatment of disease, saving lives and the enhancement of athletic performance.
1907: Pathological Cheyne–Stokes breathing (a breathing disorder) is shown to be abolished by the administration of either 100% oxygen or air enriched with more than 2% carbon-dioxide (Premby et al 1907).
1917: It is by now (in 1917) well known that the administration of oxygen produces at least some temporary benefits for patients with serious respiratory or cardiovascular problems, but the benefits aren't well described (Haldane 1917).
1920: Discovery of strong beneficial effects of the administration of air enriched with 8% carbon dioxide to patients after major surgical operations under anesthesia: circulation improves, skin color rapidly improves (pink and warm), the pulse and blood pressure quickly restore to normal and nausea and vomiting due to anesthesia are much reduced (Henderson et al 1920).
1930: It is discovered that supplying air enriched with 5% carbon-dioxide to patients in the early stages of a pneumonia attack improves their chances of survival. The earlier the patient receives the carbon-dioxide enriched air, the likelier he is to survive the attack (Henderson et al 1930).
1932: Air enriched with oxygen and carbon-dioxide is now (in 1932) used in various ways in the treatment of pneumonia, diabetes, cardiovascular problems, mental diseases and poisoning and also for respiratory and circulatory problems in the newly-born. It is also used during anesthesia, surgery and when giving birth (Salkad 1932).
1960: Konstantin Buteyko presents the results of 2 years of clinical research on nearly 200 people at the Scientific Forum at the Institute of Experimental Biology and Medicine of the USSR Academy of Science. It shows that carbon-dioxide levels and blood oxygenation can be effectively improved using an especially designed breathing exercise program. This program reverses many chronic disease symptoms, improves quality of life and decreases the need for medication usage. In 1968 he presents the final results of 10 years of laboratory research on thousands of people.
Some of the latest developments and insights on the therapeutic effects of better breathing and improving carbon-dioxide and oxygen levels.
1980: Buteyko Breathing is officially recognized as a very effective treatment for asthma by the Soviet Health Ministry after trials conducted at the First Moscow Institute of Pediatric Diseases. The trials show a 100% success rate. All hospitals in the Soviet Union are mandated to provide Buteyko Breathing training to all asthma patients.
1987: Modern research confirms the old notion that nasal breathing (as opposed to mouth breathing) plays a critical role in the regulation of breathing. Mouth breathing during sleep causes sleep-apnea, fatigue, snoring, daytime sleepiness, nightmares, restlessness, low quality of sleep and attention disorders (P. Lavie 1987).
1988: Symptoms of acute mountain sickness (such as headaches, nausea, drowsiness and weakness) are rapidly relieved by means of air enriched with 3% carbon-dioxide. Cerebral blood flow increased by 17-39% meaning that oxygen delivery to the brain considerably improved. (Harvey et al 1988).
1988: People with asthma breathe more (higher minute volume) and have lower CO2 levels than the average person (Hormbrey et al 1988).
1991 - 1997: Immersing the lower leg and feet in carbon-dioxide enriched water (topical CO2 application) results in vasodilation, increased bloodflow in the microarteries in the skin and higher oxygen utilization in the skin (due to oxygen dissociation as predicted by the Bohr Effect) (Hartmann et al 1991, Hartmann et al 1997).
1997: Raising blood carbon-dioxide levels virtually eliminates central sleep-apneas. The occurrence of central sleep-apneas during sleep is due to an acute low carbon dioxide level in the blood (Xie et al 1997).
1998: The first Western blinded randomized controlled trial on Buteyko Breathing for asthma patients finds that Buteyko reduces asthma symptoms, lowers minute breathing volume, lowers medication use and improves quality of life for asthma patients. Asthma symptoms were reduced by 80% while medication use was lowered by respectively 96% (bronchodilator medication) and 49% (steroid medication). The reduction in medication use was related to the proportionate reduction in minute breathing volume (Bowler et al 1998). Many later studies replicated these findings, for example: McHugh et al 2003, Cowie et al 2008, Prem et al 2012.
2001: Buteyko Breathing by patients being treated for breast cancer (T1-2N1M0) results in steadily increasing carbon-dioxide levels over time, lower minute breathing volume, reduced inflammatory and allergic processes in the upper respiratory airways, lower blood pressure, less frequent chest pains, a higher 3-year survival rate, better quality of life, better capacity for work, reduced fear of unfavorable outcomes of the treatment, easier social adaptation as well as relief of edema (swelling) of the upper extremities (Paschenko 2001).
2003: Repeated use of extended breath holds increases the body’s production of endogenous antioxidants and raises the anaerobic threshold, thus increasing capacity to exercise at higher levels of exertion. (Joulia et al 2003).
2005: Raising carbon-dioxide levels increases metabolic activity of alveolar microphages (neutrophils), boosting the immune system (Lang et al 2005).
2009: Raising carbon-dioxide levels attenuates endotoxin-induced gut barrier dysfunction (improves leaky gut syndrome) (Morisaki et al 2009).
2009: Buteyko improves hyperventilation-induced hypocapnia (low carbon-dioxide due to hyperventilation) and breathlessness after exercise for asthmatics (Austin at al 2009).
2009: Cells adapt to hypoxia (reduced oxygen supply) by shifting their energy generation pathway from aerobic (burning oxygen) to anaerobic (without burning oxygen) (Semenza 2009). Aerobic metabolism is preferred as anaerobic metabolism produces waste molecules that can impair muscle contractions.
2010: Reduced oxygen supply (hypoxia) strongly amplifies the body's inflammatory responses, contributing to chronic inflammation. (Imtiyaz & Simon et al 2010).
2011: Air enriched with 5% carbon-dioxide is a potent, fast-acting anticonvulsant and suppresses seizures in epilepsy patients (Toler et al 2011).
2013: Buteyko Breathing improves nasal (sinusitis) symptoms and the quality of life of asthmatics (Adelola et al 2013).
2014: The British Thoracic Society (BTS) gives Buteyko Breathing a rating of "1++" on its level of evidence (highest possible score) and an “A” on its grade for recommendation (highest possible score) in its British guideline on the management of asthma. The British Thoracic Society is a British group of respiratory medical professionals which composes treatment guidelines for doctors and healthcare professionals