The international medical norm for breathing is 6 l/min at rest. A group of Italian medical researchers from the University of Ancona reported in the Chest magazine that 28 patients with diabetes breathed from 10 to 20 l/min (Tantucci et al, 1997).
A more recent 2003 study found that 26 adult, nonobese diabetics had minute ventilation from 11.9 to 16.7 l/min (Bottini, 2003). Hence, diabetics breathe 2-3 times more air than the medical norm.
Overbreathing (or hyperventilation) provides our tissues with LESS oxygen. This is a known medical fact, which is easy to check. Start heavy and fast breathing through the mouth, and you will faint or pass out in 1-3 minutes due to low oxygenation of the brain. This fact is confirmed by dozens of studies and present in many medical textbooks. Generally, the lighter and easier your breathing, the more oxygen your body has. Why less oxygen for more breathing? There are two main causes:
1) constriction of arteries and arterioles due to CO2 deficiency (A review of medical studies that confirmed vasodilatory properties of CO2 can be found here: http://www.normalbreathing.com/CO2-vasodilation.php)
2) the suppressed Bohr effect, when red blood cells cannot release enough oxygen in tissues due to the same CO2 deficiency. (For more details and medical references related to the Bohr effect, visit: http://www.normalbreathing.com/CO2-Bohr.php)
Apart from tissue hypoxia, the pancreas gets less blood supply, permeability of cells to glucose is impaired, and sensitivity of cells to insulin is reduced. The degree of these effects is individual, but all these abnormalities are possible only in conditions of chronic over-breathing.
This hypoxia in diabetics is even more severe during nights and early morning hours. Consider this scientific quote, "Circadian rhythms of tissue oxygen balance and blood rheological properties were investigated in 40 patients with insulin dependent diabetes mellitus... Preserved blood hyperviscosity and increasing tissue hypoxia at night indicated stable disturbance of hemorheological properties and tissue oxygen balance" (Galenok et al, 1988)
It is not a surprise then that US scientists from the Brown Medical School in Providence recently published a study "End-tidal carbon dioxide predicts the presence and severity of acidosis in children with diabetes" (Fearon & Steele, 2002). They start this publication with, "Patients with diabetic ketoacidosis (DKA) hyperventilate, lowering their alveolar (PACO(2)) and arterial carbon dioxide (PaCO(2))". Their conclusion was, "End-tidal CO(2) is linearly related to HCO(3) and is significantly lower in children with DKA" (Fearon & Steele, 2002).
A group of about 200 Russian MDs have been practicing the Buteyko self-oxygenation breathing therapy for over 40 years. These doctors found that when diabetics start to slow down their heavy breathing, they need less insulin. Moreover, if they manage to normalize their breathing pattern, all symptoms of diabetes disappear. However, it may take months or years to get to the norm.
Factors that make breathing heavier and body oxygenation less are very individual. For severely sick people breathing through the mouth and sleeping on one's back are frequent problems. Posture, stress, overeating, infections, and dozens of other parameters affect our breathing.
Bottini P, Dottorini ML, M. Cordoni MC, Casucci G, Tantucci C, Sleep-disordered breathing in nonobese diabetic subjects with autonomic neuropathy, Eur Respir J 2003; 22: p. 654-660.
Fearon DM, Steele DW, End-tidal carbon dioxide predicts the presence and severity of acidosis in children with diabetes, Acad Emerg Med, 2002 Dec; 9(12): 1373-1378.
Galenok VA, Krivosheeva IA, Dikker VE, Krivosheev AB, Desynchronization of circadian rhythms of the oxygen balance in the tissues and rheological properties of the blood in type I diabetes mellitus [Article in Russian], Therapy Archives 1988; 60(9): 27-31.
Tantucci C, Scionti L, Bottini P, Dottorini ML, Puxeddu E, Casucci G, Sorbini CA, Influence of autonomic neuropathy of different severities on the hypercapnic drive to breathing in diabetic patients, Chest. 1997 Jul; 112(1): 145-153.