The relative importance of dietary patterns vs. macronutrient composition in affecting energy intake and body weight remains uncertain. In this study we propose to investigate the relative effects of dietary variety vs dietary fat on voluntary energy intake in adults. We will quantify and compare the effects of typical ranges of variety & fat intakes in the American diet on voluntary energy intake. The primary hypotheses to be tested are 1)an increasing availability of entree/side/snack/dessert variety offered will significantly increase voluntary energy intake in a dose-response fashion when other dietary factors known to influence energy intake are held constant. 2)The separate effects of dietary variety & dietary fat on energy intake will be similar.

We anticipate that the results of this investigation will lead to a greater understanding of the relative importance of eating patterns versus macronutrient composition in the etiology of obesity, and more specifically, dietary variety versus dietary fat in determining energy intake. More importantly, it will help lay a foundation for improved dietary recommendations concerning weight loss and prevention of excess weight gain in adulthood.

The relative importance of dietary patterns vs. macronutrient composition in affecting energy intake and body weight remains uncertain. In this study we propose to investigate the relative effects of dietary variety vs dietary fat on voluntary energy intake in adults. We will quantify and compare the effects of typical ranges of variety & fat intakes in the American diet on voluntary energy intake. The primary hypotheses to be tested are 1)an increasing availability of entree/side/snack/dessert variety offered will significantly increase voluntary energy intake in a dose-response fashion when other dietary factors known to influence energy intake are held constant. 2)The separate effects of dietary variety & dietary fat on energy intake will be similar.

We anticipate that the results of this investigation will lead to a greater understanding of the relative importance of eating patterns versus macronutrient composition in the etiology of obesity, and more specifically, dietary variety versus dietary fat in determining energy intake. More importantly, it will help lay a foundation for improved dietary recommendations concerning weight loss and prevention of excess weight gain in adulthood

Inclusion Criteria: Healthy adults age 18-5 y with BMI 20-35 kg/m