Diets to promote weight loss are generally divided into four categories: low-fat, low-carbohydrate, low-calorie, and very low calorie. Several diets are effective. A meta-analysis of six randomized controlled trials found no difference between three of the main diet types (low calorie, low carbohydrate, and low fat), with a 2–4 kilograms (4.4–8.8 lb) weight loss in all studies.At two years these three methods resulted in similar weight loss irrespective of the macronutrients emphasized. High protein diets do not appear to make any difference. A diet high in simple sugars such as those in soft drinks increases weight.There is evidence that dieting alone is efficient for weight loss and improving health for obese individuals.
