The current research trial is designed to compare two energy reduced (hypocaloric) diets. One diet will include one Hass avocado/day, while achieving a 500 kcal/day energy reduction. The other diet will follow a usual American diet pattern, but will also include an energy restriction of 500 kcals/day. Parameters to be explored include weight loss, satiety, dietary quality, changes in body composition and risk factors for chronic disease.