How would you answer the question, “what makes a person happy and healthy?”

Way back in 1942, researchers at Harvard began intensely studying a cohort of 268 male students, to try to deduce the factors that lead to long-term physical and mental well-being. The students were subjected to an extensive battery of physical tests that measured their bodies, organ functions, electrical activity in the brain, and overall fitness. They were also interviewed extensively by psychiatrists, and had their handwriting analyzed. Social workers were sent to their parents’ homes to obtain detailed medical and social histories of each subject and his extended family. And then, over the next 78 years, each subject filled out a survey every 2 years, underwent a physical every 5 years, and were interviewed every 15 years.

Many of the subjects became highly successful. One went on to become a bestselling novelist, four ran for the Senate, one was a cabinet Secretary and many were business leaders. Though they are anonymous, we know that one of them was Ben Bradlee of the Washington Post, because he identified himself. Another whose identity we know was a President of the United States (John F. Kennedy, whose files have been sealed, so you won’t get to read about his “physical characteristics” until 2040). But for some of the subjects it wasn’t an easy road. By 1948, 20 of the respondents were suffering from severe psychiatric difficulties. By the 1960’s one-third of the cohort was showing signs of some mental illness. One subject – Case Number 47 – fell down drunk and died.

Some of the factors that caused such negative outcomes were easy to deduce, such as smoking and drinking too much. Many of the subjects served in World War II, and those who saw combat had a much less healthy and enjoyable later life than those who didn’t. Pessimists suffered physically in comparison with optimists. And the real killer – literally – was depression: of the subjects who were diagnosed with depression by age 50, more than 70 percent were dead or dying by age 63.

And what about the good stuff, those things that lead to a long and happy life? Researchers can point to seven positive factors: education, a healthy weight, exercise, a stable marriage, no smoking, no abusing alcohol and “adapting well.” Subjects who scored high on five or six of these factors at age 50 had a 50% chance of living to 80 and being “happy/well”. But those who had three or fewer of these factors were three times less likely to live to 80.

Finally, at the center of all that data, the researchers found a sweet spot: relationships. The single most predictive factor for a long and happy life was the quality of the subject’s relationships. Good relationships with siblings were especially powerful; 93% of the subjects who enjoyed a good relationship with a brother or sister were still going strong at age 63. Asked to summarize the key finding of this study, the lead researcher responded, “The only thing that really matters in life are your relationships to other people.”

Hey, this is a Harvard study.  It must be true. So, in support of the research AND with a healthy dose of self-interest, we’d like to consider you all part of the family.

Be well, brothers and sisters!