Effects of Nutritive and Non-Nutritive Food Form and Learning on Cephalic Phase Responses

This study has two main aims: 1) To determine if ingestion of solid or beverage food forms will change appetite hormone responses, and 2) To determine whether "learning" (defined as 2 week daily consumption) about the metabolic consequence of ingesting solid or beverage foods forms varying in energy alters appetite hormone responses.

Beverage consumption has been implicated in the problem of obesity. However, the exact relationship between beverages, lower appetitive response and lower compensatory dietary responses remains unclear. This study aims to address this gap in the research. For aim 1, the null hypothesis is that the energy in beverage and solid forms will not affect appetite hormonal responses differently. The alternative hypothesis is that exposure to the energy-yielding beverage will elicit a lower appetitive hormone response compared to oral exposure to the solid food form. For aim 2, the null hypothesis is that learning will not change appetite hormone responses. The alternative hypothesis is that learning will decrease appetite hormone responses in the non-energy-yielding beverage more than in the energy-yielding beverage.