Low-carbohydrate diets: The carbohydrate content of the diet
is an important determinant of short-term (less than two weeks) weight loss.
Low (60 to 130 grams of carbohydrates) and very low-carbohydrate diets (zero to
60 grams) have been popular for many years. [2] Rapid weight loss occurs,
primarily due to glycogen breakdown and fluid loss rather than fat loss.
Low and very low-carbohydrate diets are more effective for
short-term weight loss than low-fat diets, although probably not for long-term
weight loss. If a low-carbohydrate diet is chosen, healthy choices for fat
(mono and polyunsaturated fats) and protein (fish, nuts, legumes, and poultry)
should be encouraged because of the association between saturated fat intake
and risk of coronary heart disease.
Very low-calorie diets: Diets with energy levels between 200
and 800 kcal/day are called "very low-calorie diets," while those
below 200 kcal/day can be termed starvation diets. The basis for these diets
was the notion that the lower the calorie intake the more rapid the weight
loss, because the energy withdrawn from body fat stores is a function of the
energy deficit. Starvation is the ultimate very low calorie diet and results in
the most rapid weight loss. Although once popular, starvation diets are now
rarely used for treatment of obesity.
High protein diets: Some popular books recommend high
protein diets. The effectiveness over long term has not established yet.
Mediterranean diet: The term Mediterranean diet refers to a
dietary pattern that is common in olive-growing areas of the Mediterranean
area. Although there is some variation in Mediterranean diets, there are some
common components that include a high level of monounsaturated fat relative to
saturated, moderate consumption of alcohol, mainly as wine, a high consumption
of vegetables, fruits, legumes, and grains, a moderate consumption of milk and
dairy products, mostly in the form of cheese, and a relatively low intake of
meat and meat products.
Thus, any diet that is adhered to will produce modest weight
loss, but adherence rates are low with most diets. Although a low-carbohydrate
diet may be associated with greater short-term weight loss, superior weight
loss in the long-term has not been established. The optimal mix of
macronutrients likely depends upon individual factors. A principal determinant
of weight loss appears to be the degree of adherence to the diet, irrespective
of the particular macronutrient composition. Behavioral modification to improve
dietary compliance with any type of diet may have the greatest impact on
long-term weight loss.
