The study has a duration of 35 weeks for each participant. Subjects will be first assigned to a North American control diet that they will consume for five weeks under isocaloric, weight-maintaining conditions. Participants will then consume the MedDiet for 5 weeks, again under isocaloric, weight-maintaining conditions. All foods will be provided to participants during these consecutive 5-week diets. Participants subsequently will then undergo a 20-week weight loss period in free-living conditions during which they will be given advice on how to create a 500 kcal deficit in their daily energy intake. The last phase of the study consists of a second 5-week MedDiet consumed under feeding, weight stabilizing conditions. Metabolic studies and CHD risk factor assessment will be performed at the end of each experimental diets. Metabolic studies include the measurement of in vivo kinetics of apolipoprotein (apo)B-containing lipoproteins including small dense LDL, apoCIII, HDL (apoAI) and C-reactive protein (CRP) as well as indirect measures of cholesterol absorption and synthesis.