Probably the most contentious issue in nutrition is what diet is best for promoting safe and effective body fat losses. The position of most dieticians is that a balanced diet replete in various essential nutrients, but with a reduction in total caloric intake that is proportional to daily activity levels, is the safest and most effective route to weight loss. Exercise is also added to the mix, since exercise burns off ingested calories, thus allowing one to both oxidize excess body fat, as well as eat a greater quantity of food. Still, losing weight in the standard "balanced diet" way is never easy. One reason for this is that the body fights weight-loss efforts through such mechanisms as increased appetite, making long-term compliance to most diets a challenge that is met by a few. Indeed, studies show that about 97% of those who have lost weight on a diet gain it all back within 5 years. But of all the common weight-loss diets, the one that is by far the most controversial is the low carbohydrate diet. Even the term, "low carbohydrate diet" arouses arguments about which is the best way to use such diets, or what a low-carb diet is. The usual definition of a typical low-carb diet is one that varies from 20 to 100 grams of carbohydrate a day or a diet that contains 20% or less of total daily caloric intake as carbohydrate. Some diets that are called "low carb diets," contain much higher levels of carbs, up to 100 grams a day or more. However, these higher carb diets are not actual low carb diets, since any intake of carbohydrates over 50 grams is no longer a true low carb diet.
Adding to the confusion is the fact that there are two basic types of low-carb diets. The first one is the low carb plan just described, containing a maximum daily intake of 50 grams of carbohydrates, with gradual increases in carb intake depending upon carb tolerance to 100 grams or so. The other type, often confused with the common low-carb plan, is the ketogenic diet. The ketogenic diet is more accurately described as a "no-carb diet," since on this diet, you cannot consume more than 20 grams of carbohydrates a day. The diet derives its name from the rise in ketones, which are metabolic acid byproducts that result from incomplete fat oxidation. The ketogenic diet is the most extreme form of low-carb dieting, since it allows virtually no carbs at all, with all caloric intake instead coming from a combination of protein and fat. In the past, the ketogenic diet was used as an effective therapy to treat cases of epilepsy, but this has largely been discarded with the advent of more effective drugs to treat the disease. The main controversy about the ketogenic diet is the . . .