Social relationships keep older people healthy, and the marriage relationship is especially beneficial. A growing body of research helps explain how social interaction interacts with social, physical, and psychological factors that affect an individual's health, and the importance of maintaining social networks and relationships later in life. Social relationships and interaction are associated with a wide range of health benefit, especially in older ages. The benefits of marriage extend beyond the daily social interaction and the shared network of family and friends. Sociologist and demographer Linda Waite discussed her research on these interactions with PRB.