Ketosis is a metabolic state in which the liver converts fat into vetoes and ketone structures, which can then be used by the body for energy. This should not be confused with “ketoacidosis“, which is a dangerous condition that can occur with diabetes. Ketosis is a condition we want to achieve in order to lose weight. Ketones are molecules produced by the liver during fat metabolism and are a normal source of fuel and energy for the body. Diets that limit calorie intake cause weight loss, but some of the weight loss is fat and some fat from muscle tissue. Loss of lean muscle tissue slows down the metabolism, making it difficult to lose weight as well as lose weight.
When your body is in ketosis, it uses fat as its primary source of energy. If you eat enough protein, your body will not break down muscle tissue. Once the liver has converted fat into ketones, it cannot be converted back into fat and stored, so your body needs to excrete your sweat and urine molecules.
Many people mistakenly believe that they can not or will not lose weight because ketones fall to lower levels. This means that the ketones used to measure ketones in urine do not show a purple test strip, but weight loss remains with or without ketones. Excess ketones released into the urine are lost on a low carbohydrate diet after the body becomes accustomed to using dietary fats for energy instead of glucose. This usually happens within a few weeks after dieting. People who eat mostly carbohydrate-rich meals have their bodies sugar and fructose derived from carbohydrates. Their cells have had very little experience in burning fatty acids for energy. The body first uses glucose to prevent high blood glucose levels.
The body experiences a new state when a person goes on a low carbohydrate diet. The most widely used glucose fuel is no longer available. The body responds by adding the production of pancreatic insulin and glucagon. Glucagon attracts stored fat sources in the form of triglycerides for use by cells as a new energy source. However, cells respond slowly to this new source of fuel, and the individual feels weak or lacks energy. Resistance to fatty acids for energy can vary greatly between individuals. Some people feel their weakness, while others feel more energized than before.
The liver begins to catabolize (break down) excess fatty acids that are not used by the cells. However, the liver does not have the enzyme needed for complete catabolism of fatty acids. This causes ketone molecules to leak into the bloodstream. A strange taste in the mouth and a slight odor of breath indicate the presence of these ketones. Other cells in the body can use ketones for energy. The brain can also use ketones, contrary to the myth that the brain can only use glucose; although some areas of the brain still need glucose, which the body produces from amino acids or fats. After a few weeks, the body begins to use fatty acids more efficiently for energy and ketone levels return to normal. This does not mean that weight loss is not. This means that the body becomes a more effective fat burner.