Richard Bender

Grant Type

Dissertation Fieldwork Grant

Institutional Affiliation

Colorado, Boulder, U. of

Grant number

Gr. 9379

Approve Date

October 12, 2016

Project Title

Bender, Richard L., U. of Colorado, Boulder, CO - To aid research on 'Do Protein Content and Protein Quality Influence Human Food Intake? Testing the Protein Leverage Hypothesis,' supervised by Dr. Darna Dufour

Preliminary abstract: Why do people eat what they eat? One of the most important goals of nutritional anthropologists is to seek answers to this deceptively simple question. In this research, I will test the Protein Leverage Hypothesis (PLH), an explanatory framework that my help us understand how broad-scale dietary changes influence individual human food intake. The PLH suggests that all animals, including humans, prioritize the intake of protein over the intake of carbohydrates or fat. This means that if a diet is high in protein, people will eat less food overall, since they can meet their protein requirements easily. On the other hand, if a diet is low in protein, people will tend to eat more food overall as they attempt to consume enough protein. The PLH has important implications for contemporary human nutrition: as our diets are becoming increasingly dominated by processed, high-carbohydrate, low-protein foods, people will tend to overeat, and this will contribute to obesity. To test the PLH, I will conduct an experiment in which adult humans subsist for 48 hours at a time on one of four custom-designed liquid diets. These liquid diets, which will be similar to commonly-available protein shakes, will be identical in taste, smell, and appearance, but they will differ in both protein content and protein quality (i.e., animal protein vs. plant protein). By measuring how much of the liquid diet people consume over 48 hours, I will be able to test whether people take in less food overall on a high-protein diet, and more food overall on a low-protein diet. This experiment will be an improvement over previous tests of the PLH, and will allow for a clearer analysis of how protein affects food intake.