Understanding Ketosis

First, a simple explanation of the process: the carbohydrates you eat are converted to glucose, which is the body's primary source of energy. Whenever your intake of carbohydrates is limited to a certain range, for a long enough period of time, you reach a point where your body draws on its alternate energy system, fat stores, for fuel. This means the body burns fat and turns it into a source of fuel called ketones. (Ketones are produced whenever body fat is burned.)

When you burn a larger amount of fat than is immediately needed for energy, the excess ketones are discarded in the urine. Being in ketosis means your body has burned a large amount of fat in response to the fact that it didn't have sufficient glucose available for energy needs.

Dietary ketosis is among the most misunderstood concepts in nutrition because it is often confused with ketoacidosis, which is a life-threatening condition most often associated with uncontrolled insulin-deficient type 1 diabetes. In the type 1 diabetic, the absence of insulin leads to a toxic build-up of blood glucose and an extreme break-down of fat and muscle tissue. This condition doesn't occur in individuals who have even a small amount of insulin, whether from natural production or artificially administered.

Dietary ketosis, however, is a natural adjustment to the body's reduced intake of carbohydrates as the body shifts its primary source of energy from carbohydrates to stored fat. The presence of insulin keeps ketone production in check so that a mild, beneficial ketosis is achieved. Blood glucose levels are stabilized within a normal range and there is no break-down of healthy muscle tissue.

The most sensitive tests of ketosis ("NMR" and "blood ketone level") show that everyone is in some degree of ketosis every day, particularly after not eating overnight and after exercising. Ketosis is the body's survival system. It is not an abnormality, nor does it present any medical danger, except to a type I insulin-dependent diabetic. The body functions naturally and effectively while in a state of dietary ketosis.

Some of the benefits many people experience while in a state of dietary ketosis for intentional weight loss may include rapid weight loss, decreased hunger and cravings, improved mood, increased energy and, as long as protein intake is adequate, protection of lean mass.