The longest study of a good life

In 1938, a project began at Harvard that was designed to run so long that none of the people involved would live to see the end of it. A group of researchers wanted to know what makes a person grow old in good health and good spirits. Not in theory, but measured against real biographies.

They enrolled 268 sophomores from the university, all male, all privileged. A little later a second group joined: 456 boys from the poorer neighbourhoods of Boston, many from families with no money and no prospect of higher education. Participants were interviewed, examined and visited at home across decades. Blood work, medical records, interviews with their spouses, later with their children. The study still runs today and now follows more than a thousand descendants of the original participants.

It is the longest investigation into the course of human lives that exists. And its clearest finding fits into one sentence.

“Good relationships keep us healthier and happier. Period.”

That is how Robert Waldinger, since 2005 the study’s fourth director, sums up the result. Not wealth. Not fame. Not cholesterol. The single best predictor of how someone would be doing at eighty was how satisfied they were with their relationships at fifty.

At first glance this is the sort of insight you nod at and forget, because it sounds so obvious. It gets interesting in the details.

It is not about the number. People with many contacts were not automatically better off. What mattered was whether there were people they could rely on when things got hard. A few dependable relationships beat a large network of acquaintances.

Loneliness works on the body. Participants who felt isolated saw their health decline earlier, their brain function fade faster, and they died younger. And it was about the feeling, not the objective situation. You can be lonely in the middle of a family.

Conflict costs more than coldness. Marriages with a lot of argument and little warmth turned out to be particularly bad for health, in some cases worse than a divorce. Closeness itself is not the protective factor. Dependable closeness is.

Why this is so hard to believe

The researchers regularly asked the young participants what they wanted to work towards in life. Over eighty percent named wealth, and a large share added fame. Relationships rarely made the top of the list.

That is not a flaw of character. It is because relationship work is invisible. A promotion has a date. A bank balance has a number. A phone call to an old friend has neither. It leaves no receipt you could hold up, and its benefit only shows across decades.

There is also this: relationships are demanding and messy. They take time, they come with disappointments, and they cannot be finished. A fitness programme has an end. Friendship does not.

The practical consequence is smaller than you think

In their book about the study, Waldinger and his co-author Marc Schulz describe something they call social fitness. The idea: relationships behave like muscle. They waste away when unused, and nobody would seriously suggest that training once is enough for a lifetime.

What follows from that is unspectacular. No overhaul of your life, no relationship project. Just regular, small movement. A phone call instead of another round of scrolling. A message to someone you were thinking about anyway.

Over 85 years of research, thousands of people, millions of data points. And at the end stands a recommendation that needs no budget and no preparation: get in touch with the people who matter to you. Regularly. For as long as you can.