What is the secret to weight loss? You increase energy output, by exercising more. Or you decrease energy input, by dieting. And the diet that you follow will usually focus on decreasing the intake of one or more of either fats, carbs, calories or protein. So far, so good. But do you know what a major problem is with most diets? Each one will be based on a study that someone has conducted on a group of people. But it’s quite difficult to accurately control the input and output of energy of a large population, so a lot of the research into dieting is based on a very small number of people that are watched very closely for a very short time. Or it’s based on a larger group of people who record their own statistics. And people are notoriously dishonest when it comes to owning up to what they’ve eaten or drunk or the amount of exercise they’ve done.

A team of American researchers got around this problem by paying 25 people to live in isolation for three months and strictly monitoring both energy intake and expenditure. The first month was spent finding out exactly how many calories were needed to maintain body weight – neither gaining nor losing weight. Then for the next two months they were fed diets that contained 40% more than was required, made up of different combinations of fats and protein.

What they found was that once you have consumed your daily requirements any excess at all will cause a gain in body fat. But if the excess is in the form of protein it will cause an increase in both fat and muscle, whether exercise is performed or not.

The results indicate that when trying to lose weight by reducing the intake of calories the most effective strategy would be to have a diet made up of more protein than fats, which will maintain muscle mass but reduce body fat. And that’s a healthier way of losing those excess kilos.