Ketone Bodies and Effective Weight Loss
Consistent overeating invariably results in weight gain, no matter what the source of the excess calories may be: carbohydrates, lipid, protein, or even alcohol. When you gain weight, your adipose tissue tends both to add more cells and to enlarge the ones already there. Severely obese people are unequivocally known to have added cells. Obese children, even those who are not necessarily extremely overweight, also add more adipose cells. Obese children retain those added cells for life. During weight loss, the existing cells merely shrink, so many little “starving” cells remain just waiting for a chance to grow again. The existence of these starving cells may explain why many people tend to regain weight so easily.
Most of the time, the body cells depend on glucose from the blood for their energy. Overnight, when carbohydrate levels in the blood decrease, blood proteins are degraded in the liver to convert them to glucose; adipose tissue is also degraded to some extent. In the course of a diet, the body begins to break down muscle mass (protein) for conversion to glucose. After a few days to a week, nitrogen depletion becomes excessive. The body turns away from sources of glucose and turns to fats in adipose tissue. These fats are metabolized to fatty acids and glycerol, with the glycerol available for conversion to glucose, taking care of special-ized tissues with a specific requirement for glucose.
The fatty acids are converted to short-chain oxy acids usually called ketone bodies, such as β-hydroxybutyrate and β-ketobutyrate, which are highly water soluble and are circulated easily in the blood. The ketone bodies are efficient nutrients because they enter directly into the mitochondria for aerobic metabolism. The heart uses ketone bodies all the time. Adipose tissue surrounds the heart and even permeates into it, providing a direct and efficient energy supply for this constantly working tissue. The brain adapts to the use of ketone bodies as nutrients after about a week of fasting. This was a surprising observation because it had been believed that the brain could only use sugars. At this point, weight loss becomes very effective.
Why do you lose weight so effectively? Part of the answer depends on the fact that the ketone bodies are potentially dan-gerous because they are relatively strong organic acids and they lower the blood pH, possibly causing acidosis. Recall that at low pH, hemoglobin is less able to bind oxygen. If you drink lots of fluids, your kidneys flush out the ketones in the urine to adjust body pH. You lose weight very efficiently at this point because you are literally putting excess calories “down the drain.” The water in Dr. Stillman’s Water Diet was there for a reason.
It is important to note that prolonged ketosis/acidosis can be dangerous or even fatal. One reason is that the excess urination could produce a secondary mineral imbalance, and this is danger-ous, especially if one has a weak heart. Medically supervised diets try to avoid a true ketotic state, and people on such a limited-calorie diet should be under constant physician care. You can tell that you are in extreme ketosis by the metallic taste (acetone breath) in your mouth when you get up in the morning.