Testing the Protein Leverage Hypothesis in a free-living human population.

The Protein Leverage Hypothesis (PLH) predicts that humans prioritize protein when regulating food intake. We tested a central prediction of PLH: protein intake will remain more constant than fat or carbohydrate in the face of dietary changes in a free-living population. Data come from a large sample of adult Filipino women participating in the Cebu Longitudinal Health and Nutrition Survey (CLHNS) located in Philippines. Longitudinal data analysis showed that, as predicted, calories of dietary protein remained more constant over time than calories of dietary carbohydrates or fat, even if corrected for the low proportional contribution of protein to dietary energy.