There used to be a saying that “fat is fat.” Dietitians and cardiologists conspired to convince Americans that the growing problem of weight gain was due to “energy-dense” foods. Of the three macronutrients (fat, carbohydrates and protein), fat has the greatest energy density with 9 calories per gram, as opposed to 4 calories per gram for carbohydrates or protein. While it is true, at the most basic level, that someone consuming 500 grams a day of food will gain much more if it is all fat (4,500 calories) as opposed to sugar (2,000 calories), most people do not base their eating on the total mass (grams) consumed.

There are (generally) hedonistic people who eat what they crave; those who mechanically sit down at mealtime and eat what is necessary to get past the social/physical feeding requirement; or compulsive individuals who track total calories, points, carbohydrate grams, etc. [Note: this compulsion can be positive or pathologic depending upon the degree of influence it has on a person’s behavior and psyche.]

           In typical, extreme fashion, the American public fled low-fat diets to flock toward the Atkins diet, which is the macronutrient antithesis (opposite) of the low-fat diets. During the induction phase of the Atkins diet, clients are directed to eat a minimal amount of carbohydrates (around 20 grams per day) for a period of approximately two weeks. The diet during this time is predominantly fat (by calorie), yet results in dramatic and rapid weight loss for most who follow the restrictions closely; much of the initial weight lost is water that normally is associated with stored glycogen (sugar) or retained due to the metabolic effects of insulin. Long-term weight loss is as good as or better on low-carbohydrate diets as the low-fat diets provide.1 A number of additional metabolic changes that promote weight loss occur in “low-carb” diets, but that is outside the scope of this article.