Ketoacidosis
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Ketoacidosis is a type of metabolic acidosis which is caused by high concentrations of keto acids (formed by the deamination of amino acids) and of ketone bodies (formed by fatty acid metabolism. This is most common in untreated type 1 diabetes mellitus, when the liver lacks glucose but needs metabolic fuel, so metabolizes fat and proteins.
The acidity results from the dissociation of the H+ ion from the ketone bodies acetoacetate and B-hydroxybutyrate (which are produced by ketogenesis in fatty acid breakdown). Since this H+ dissociation means a higher concentration of H+ in the body, the physiological pH (which is normally around 7.4) is lowered to acidic levels. Normally, when ketone bodies are produced, they do not accumulate enough to change the body's pH. When "abnormal" levels of these ketone bodies are made, the body is in ketosis, and when the levels become so high that the pH is changed, this is when ketoacidosis occurs. The acid concentration is further increased by dehydration.
Although many low-carb diets (such as the Atkins diet) are accused of causing ketoacidosis, the condition can only be caused by more extreme conditions, such as in excessive alcohol consumption or in insulin impairment (as in diabetes). (Low-carb diets do, however, induce ketosis, which is not a normal response to reduced carbohydrate availability) Ketogenesis is well regulated by the mileau of hormones governing the fasting and fed states, predominantly glucagon and insulin, and is too mild to lead to acidosis. Ketogenesis is normal in humans. It occasionally reaches ketosis-level amounts during sleep and other times of carbohydrate shortages.
See also
External links
- The Merck Manual - Diabetic Ketoacidosis (http://www.merck.com/mrkshared/mmanual/section2/chapter13/13b.jsp)
- Alcoholic Ketoacidosis (http://www.merck.com/mrkshared/mmanual/section2/chapter13/13c.jsp)