Extremely low fat, high carbohydrate diets are also very effective for weight loss but it must be stressed that large reductions in total fat intake would be unattainable at a population level. Average changes in the order of 2–3 kg may seem small for individuals but they are important on a population level in the context of obesity prevention. A shift of one unit of BMI in the overall distribution in the population is associated with a 5% point change in the prevalence of obesity
effective