Lessons from the Longest-Running Study on Happiness

What makes us happy in life—a high-powered career? Wealth? Fame? Beauty?

The Harvard Study of Adult Development is the longest-running study on happiness. It has followed 724 men from various economic and social backgrounds since they were teenagers in 1938. Researchers collect detailed health information, and every two years ask questions about their lives, mental and emotional wellness, and interview family members.

The researchers, led by project director Dr. Robert Waldinger, professor of psychiatry at Harvard Medical School, have found that specific traits and behaviors are linked with greater happiness and fulfillment across the entire group. So what makes us happiest? High-quality relationships and social connections.

More than money or fame, it has been found that forming close, positive relationships (spouses, family, friends, social circles) and staying connected with them are what keep people happy throughout their lives. Relationships can protect people from discontent, help delay mental and physical decline, and better predict longevity and happiness than social class, IQ, or even genetics. Those with warm relationships were happier and lived longer. “Loneliness kills. It’s as powerful as smoking or alcoholism,” according to Waldinger.

Relationship satisfaction at age 50 is a better predictor of physical health than cholesterol levels. “The people who were the most satisfied in their relationships at age 50 were the healthiest at age 80,” says Waldinger. Marital satisfaction also has a protective effect on mental health, and those in unhappy marriages feel more physical and emotional pain than those in happy marriages.

It is clear that we must invest in our relationships and sense of community for health, happiness, and longevity. “The surprising finding is that our relationships and how happy we are in our relationships has a powerful influence on our health,” says Waldinger. “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.”