What follows is reflection on a long-running piece of research, not advice. We are writers and editors reading the literature, not clinicians, psychologists, or therapists. The study at the centre of this piece is observational, and patterns drawn from one cohort are not prescriptions for any single reader’s life.
In 1938, what became the Harvard Study of Adult Development began with the Grant Study, which followed 268 Harvard sophomores. It was later combined with the Glueck Study, which followed 456 boys from Boston. The study not now includes these mens’ offspring.
The aim was modest and a little vague: to watch ordinary lives unfold and learn what kept people healthy. Nearly nine decades later, it is still running, now with a broader participant base.
When the researchers pooled what they had collected and looked for what predicted a good old age, the obvious candidates underperformed. The study director, Robert Waldinger has put it this way: “When we gathered together everything we knew about them about at age 50, it wasn’t their middle-age cholesterol levels that predicted how they were going to grow old. It was how satisfied they were in their relationships.” This is a finding from one cohort, not a universal law of medicine, but within this group the relationship measure carried more predictive weight than the markers people tend to worry about.
The pattern appeared elsewhere in the data too. Participants who reported good relationships were, according to summaries of the work, associated with less heart disease, diabetes, and arthritis.
Still, the direction was consistent enough that Waldinger has summed up the headline plainly: good relationships, in his telling, keep us happier and healthier. That is a confident line, drawn from a largely white, male sample, and worth reading as one researcher’s framing of a correlation rather than a settled verdict on everyone.
Waldinger has described the result as a “surprising finding,” that our relationships and how happy we are in them appear to have “a powerful influence on our health.” Influence, not cause. The study cannot prove the arrow runs only one way, and it doesn’t claim to.
Perhaps the strangest thing about the result is how badly it travels. Waldinger’s 2015 TED talk on the study has been viewed more than 29 million times on Youtube alone, and the message is not complicated: tend your close relationships. Anyone who has let a relationship lapse because work felt more urgent has run the small experiment the study runs at scale. The advice is easy to nod at and hard to act on, partly because it competes with everything louder, salaries, titles, the next achievement.
The study’s limits are worth stating plainly, even while taking it seriously. The original cohorts were men, mostly white, and both groups were unusually narrow slices of mid-century America. The headline is a correlation built on that sample, expanded now to spouses and offspring who now number well over a thousand, but still rooted in one long, specific thread of lives. What it offers is a clue with unusual staying power, not a formula.
If the question of who you are close to, and how that is going, lands somewhere tender, a qualified counsellor or therapist is a good person to talk it through with.
The quiet implication of the study’s own length is the part that stays. It took the better part of a century, four directors, and decades of near-precarious funding to arrive at an answer many people could have guessed at the start. The difficulty was never in finding it. The difficulty is in believing something that ordinary could be the thing that matters most.
