Study Arm 1: (4 days) Following the baseline blood draw, subjects randomized to begin on the fast food arm will consume a fast food diet for 4 days, Subjects randomized to begin on the Med diet arm will consume foods provided to them and follow basic food preparation instructions. At the end of each 4-day-long diet phase, subjects will report to the Ragle Human Nutrition Research Center again for their first follow-up study visit (Study Visit 2). Participants will be required to collect another stool sample to bring with them to their visit and will complete a hunger and satiety questionnaire at either the lunch or dinner meal each day on each diet arm.