The Cleveland Clinic

Weight Loss:
High Protein, Low Carbohydrate Diets

High protein, low carbohydrate diets have been widely promoted in recent years as an effective approach to losing weight. These diets generally recommend dieters receive 30% to 50% of their total calories from protein . By comparison, the American Heart Association, the National Cholesterol Education Program and the American Cancer Society all recommend a diet in which only 10% to 15% of calories are derived from protein (nutrients essential to the building, maintenance and repair of tissues in the body).

The Atkins diet is an example of a high protein, low carbohydrate diet.

How Do These Diets Work?

By restricting carbohydrates drastically to a mere fraction of that found in the typical American diet, the body goes into a different metabolic state called ketosis, whereby it burns its own fat for fuel. Normally the body burns carbohydrates for fuel -- this is the main source of fuel for your brain, heart and many other organs. A person in ketosis is getting energy from ketones, little carbon fragments that are the fuel created by the breakdown of fat stores. When the body is in ketosis, you tend to feel less hungry, and thus you're likely to eat less than you might otherwise. However, ketosis can also cause health problems, such as kidney failure (see below).