Assessment of Energy Balance

The digital photography of foods method was developed to unobtrusively measure energy intake in naturalistic settings (e.g., cafeterias). Participants will be provided with cell-phones with digital cameras and cellular network capability. Participants were trained to take pictures of their food selection and plate waste and to send these pictures to the researchers over the cellular network. The participant will collect data in free-living conditions and these data will be collected in near real time.

Doubly labeled water, considered the gold standard for measuring energy intake in humans, was used to measure total daily energy expenditure during free-living conditions. DLW is used to obtain an accurate measure of total daily energy expenditure, which is equal to energy intake during energy balance.

The Intelligent Device for Energy Expenditure and Activity (IDEEA) will be used to measure the time spent engaging in active vs. sedentary behaviors, and the energy costs of these behaviors.

Participants will be instructed to consume five packets of Health One per day, which provides 800 kcal and 125% of Recommended Daily Intake of vitamins and minerals. Additionally participants will be instructed to consume a meal consisting of 200 kcal to 350 kcal daily, which could consist of a portion-controlled meal replacement or a home-cooked meal. Participants will meet with a Registered Dietitian at weeks 0, 2, 4, and 6 and receive instructions on adhering to the meal plan.

The Actical will be used to measure the time spent engaging in active vs. sedentary behaviors, and the energy costs of these behaviors.

The Sensewear armband will be used to measure the time spent engaging in active vs. sedentary behaviors, and the energy costs of these behaviors.