Calorie restriction in humans: An update

This paper reviewed studies of calorie restriction, meaning eating fewer calories without missing essential nutrients, in healthy adults. It examined changes in weight, blood sugar, blood pressure, cholesterol, and other health measures. In a major trial, 218 adults were asked to reduce their daily calories or keep eating as usual for two years. People who reduced calories lost weight and generally improved several health measures. The studies were too short to show whether calorie restriction helps people live longer, and severe restriction can cause hunger, muscle loss, or nutrient shortages.

What this means for you: Modest calorie reduction may improve some health measures, but it has not been proven to extend human life. Do not buy supplements or attempt extreme dieting based on this review; any lasting changes should provide enough nutrients and be safe for your health.