In 1938, the Harvard Study of Adult Development started tracking the lives of 268 sophomores to find out what the keys were to a long life. One of the original recruits, John F. Kennedy would go on to become US president.
Over the years, the study was expanded to include a few hundred more people.
They were expecting to find eating right, exercising and avoiding drugs, smoking, and alcohol would be key factors.
But the researchers were surprised to find that strong relationships, marriages and friends, were equally important to good health and long life.
Robert Waldinger, a Harvard psychiatry professor and the study’s lead researcher, said:
“It wasn’t their cholesterol levels that predicted how they were going to grow old. It was how satisfied they were in their relationships. The people who were the most satisfied in their relationships at age 50 were the healthiest at age 80.” […]
“The surprising finding is that our relationships and how happy we are in our relationships has a powerful influence on our health. Taking care of your body is important, but tending to your relationships is a form of self-care too. That, I think, is the revelation.”
It also found that strong friendships were more significant than having many casual friends.
In describing the study, writing for Harvard.edu, Liz Mineo adds:
“The researchers also found that marital satisfaction has a protective effect on people’s mental health. Part of a study found that people who had happy marriages in their 80s reported that their moods didn’t suffer even on the days when they had more physical pain. Those who had unhappy marriages felt both more emotional and physical pain.
“Those who kept warm relationships got to live longer and happier, said Waldinger, and the loners often died earlier. “Loneliness kills,” he said. “It’s as powerful as smoking or alcoholism.”