Physical activity and nutrition programs for couples: a randomized controlled trial.

Diet and physical activity habits may deteriorate after cohabitation, leading to weight gain and increased risk of lifestyle diseases. We carried out a 4-month, randomized controlled trial of a diet and physical activity program for couples with a 1-year follow-up, comparing two methods of delivery. The program used six modules, which, after an initial group session, were mailed to the low-level intervention group. In the high-level intervention group, half of the modules were mailed, and the others were delivered at interactive group sessions. A control group received no intervention. Postintervention and at follow-up, physical fitness improved in the high-level group, saturated fat intake decreased in both intervention groups, and low-density lipoprotein cholesterol fell in the high-level group. Fewer participants in the high-level group became overweight or obese. Health promotion for couples can improve health behaviors and potentially lower the risk of lifestyle diseases in participants and their future families.