Eating protein appears to boost blood concentrations of a hormone recently found to restrict appetite, researchers report. The findings could explain the success of popular high-protein diets.
Four years ago, Rachel L. Batterham of University College London and her colleagues found that injecting a hormone called peptide YY (PYY) into both normal-weight and obese people reduced their food intake by about a third and dampened hunger. A person's gut normally secretes the hormone during and after a meal.
Batterham's team wondered whether food's three basic nutrients—protein, carbohydrates, and fat—have different effects on how much PYY people secrete.