||The English used in this article may not be easy for everybody to understand. (February 2012)|
Ketosis occurs when ketone bodies are released into the bloodstream due to low glycogen levels in the liver. Ketone bodies are created by the breakdown of fatty acid. Ketosis can be understood as the use of body fat as a source of energy.
The body goes through ketosis when there is not enough carbohydrate to refill glycogen in the liver. An example of this kind of diet is the Atkins diet, where followers start by eating fewer than 20g of carbohydrates per day. It takes 48 hours for the brain to switch from glucose to ketone bodies. Ketosis helps the body prevent using protein, from muscles, for gluconeogenesis to make glucose.