More is less for protein in the diet
A study by Full4Health Partners at the University of Maastricht
Obesity results from a chronic energy imbalance, with energy intake exceeding energy expenditure. Food intake regulation is the main focus of many weight loss strategies. The role of dietary protein has received considerable attention of late in attempts to limit caloric intake.
Margriet Westerterp-Plantenga is Professor of Food Intake Regulation in Humans at the University of Maastricht. As part of the Full4Health project, she led a study* to find out whether including more protein in the diet leaves volunteers more satiated, and thus taking in less energy in the form of carbohydrates and fat. In addition, the research team wanted to know whether a diet low in protein makes volunteers more hungry to compensate for the "missing" energy contributed by protein. Volunteers were invited to consume 3 different types of diet - high, normal and low in protein - for 12 consecutive days.
Researchers Eveline Martens and Sofie Lemmens were able to demonstrate that people on the high protein diet took in less total energy during meals, whereas the low protein diet did not increase food intake. Feelings of hunger and satiety were similar between all three diets. This means that people on the high protein diet did not feel more hungry despite eating less, and had better control over their overall food intake.
*Protein leverage affecting energy intake on high protein diets in humans. AJCN 2012 [Epub ahead of print] PMID 23221572