Back in 1988, James House and colleagues reviewed a number of studies on social relationships and mortality. They concluded that “…the theory and evidence on social relationships and health increasingly approximate that available at the time of the U.S. Surgeon General’s 1964 report and smoking and health…with similar implications for future research and public policy.”¹ Since that time, the evidence has continued to accumulate. While not all studies have found an association, there is sufficient confirming evidence to take it very seriously. These findings raise three issues: Is the association causal? If it …