Many low-carbohydrate diets tout the benefits of being in a state of ketosis, which they claim results in weight loss. The idea is that by not eating enough carbohydrates to use as energy, your body will instead break down fat for energy. As a result, you will lose fat and weight. The idea of ketosis for weight loss, however, does not work as well in reality and comes with many health risks. Talk to your doctor before going on a diet that promotes ketosis.
The state of ketosis occurs when ketone bodies, which are actually three biochemicals -- acetone, acetoacetic acid and beta-hydroxybutyric acid -- build up in your bloodstream. Your body needs carbohydrates to fully break down fat, so a lack of carbohydrates in your diet leads to ketosis. It is normal for the body to produce small amounts of ketone bodies, but when placed in a state of starvation, the liver produces ketone bodies from fatty acids to nourish essential organs like the brain and heart. The excess acetone is excreted in the urine and producing the characteristic sweet breath often found in diabetics
Weight Loss Through Appetite Suppression
It is possible to lose weight in the state of ketosis, especially in the beginning. This state can reduce your feelings of hunger so you eat less, which is the result touted by low-carbohydrate diets. Ketosis might even make you nauseous, making you not want to eat. A May 2008 study in "The American Journal of Clinical Nutrition" points out, however, that not enough evidence backs up the idea that ketones suppress appetite.
Weight Loss from Additional Factors
Ketosis also might cause weight loss in the beginning of a diet because of a loss of water weight. Ketosis causes your body to get rid of sodium and to release more urine. This can result in losing about 100 to 150 calories a day, just from this aspect of ketosis. This is weight that will likely be regained, however. Many diets that result in ketosis, namely low-carbohydrate diets, are low in calories as well, which can lead to weight loss. Nonetheless, it is often an unhealthily low number of calories.
Although you might lose weight on ketosis, it is not recommended for your body. Ketosis can cause a number of side effects, including dizziness, bad breath, dehydration, constipation, headaches, weakness and irritation. After you are on it for a longer period of time, such as a few weeks, it can cause kidney stones and gout. Ketosis can cause death if you have diabetes. If you are pregnant, ketosis can interfere with the development of your baby or even cause death.
- University of the Incarnate Word: “Benign Dietary Ketosis” Is the Way to Break Through This High-Insulin Pattern and Cause Your Body to Burn More Fat
- Rutgers Cooperative Research and Extension; Fad Diets: Healthy or Hazardous???; Karen Ensle, et al.
- Weight-Control Information Network: Weight-Loss and Nutrition Myths
- The American Journal of Clinical Nutrition; Effect of Weight Loss and Ketosis on Postprandial Cholecystokinin and Free Fatty Acid Concentrations; Supornpim Chearskul, et al.