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Home » Transcript: What 85 Years of Research Says Is The Real Key To Happiness – Robert Waldinger

Transcript: What 85 Years of Research Says Is The Real Key To Happiness – Robert Waldinger

Read the full transcript of Harvard psychiatrist Robert Waldinger’s interview on The Big Think Interview on “What 85 Years of Research Says Is The Real Key To Happiness”, July 25, 2025.

Chapter 1: The 85 Year Quest to Understand Happiness

ROBERT WALDINGER: I’m Robert Waldinger. I am a psychiatrist and professor of psychiatry at Harvard Medical School. I direct the Harvard Study of Adult Development at Massachusetts General Hospital.

I became interested in psychiatry unexpectedly. I had never known a psychiatrist growing up, but when I was in medical school, I found that the way people’s minds worked was the most fascinating thing I could possibly study. So I eventually found that there was really nothing else for me in medicine but doing psychiatry.

I started out as an intern in pediatrics and I would see one ear infection after another and the kids were adorable. But one ear infection is pretty much the same as every other. Whereas when you talk to people about their lives, it’s never the same. And I knew that that would keep me interested for my whole career, which it has.

I am the fourth director of the Harvard Study of Adult Development and it is the longest study of adult life that’s ever been done. We’re in our 85th year. It started in 1938 as two studies that weren’t even aware of each other.

One study started at Harvard Student health service with 19 year old sophomores who were thought by their deans to be fine, upstanding young men. And the other study was a study of juvenile delinquency. And it selected boys middle school age from Boston’s poorest families, but also the most troubled families, families beset by problems like domestic violence and parental mental illness and physical illness.

This study set out to understand what makes people thrive as they grow and develop. And that was unusual because most research that’s been done is done on what goes wrong in human development so that we can help people. But this was a study of what goes right. So it was how do kids from disadvantaged families stay on good paths and develop well? And then of course, the very privileged Harvard group was meant to be a study of normal young adult development.

We now know that if you want to study normal young adult development, you don’t just study white men from Harvard, but at that time that’s what they did. We study well being as people go through life. And our big question is if you could make one choice today to make it likely that you would stay happy and stay healthy throughout your life, what single choice would you make?

And most of us think it’s something to do with getting rich or achieving a lot. And some people even think they need to become famous to have a healthy, happy, healthy life. But our study and many other studies show that the single choice we can make that’s most likely to keep us on a good path of well being is to invest in our relationships with other people.

The people in our study who had the happiest, warmest relationships were the people who stayed healthy longest and who lived the longest.

The Harvard study started in 1938 and it has followed the same people throughout their entire lives, from the time they were teenagers all the way into old age. The study began with 724 young men, and then we brought in most of their wives and eventually most of their children. So that now there are over 2,000 people in these 724 families who we have followed through their entire adult lives.

We started collecting information by giving these young men elaborate psychological examinations, also medical examinations. Then we went to their homes, we talked to their parents, and sometimes even their grandparents. And the workers made elaborate notes about what was being served for dinner and what the discipline style was in the family and even what the curtains looked like.

And then eventually, as new methods of studying human life came on board, we adopted those methods. So audiotaping, videotaping, we now draw blood for DNA. And DNA wasn’t even imagined in 1938 when the study began. We’ve put many of our people into an MRI scanner and watched how their brains light up as we show them different visuals, images.

We bring them into our laboratory and we deliberately stress them out. And then we watch how they recover from stress as one more way of understanding well being. One of the things that is more common now, but was unusual when we started, it was combining biological measures and psychological measures and seeing how our biology is influenced by our mental states and vice versa. So it’s this combining of mind and body measurement that was relatively new in the last 20 years.

The question comes up how much of our happiness is under our control? And they’ve actually done some scientific analyses of this. A psychologist named Sonia Lyubomirsky did an analysis in which she estimates that about 50% of our happiness is a kind of biological set point probably determined by our genes that has to do with inborn temperament.

We all know people who are kind of naturally gloomy and other people who are naturally chipper no matter what’s going on. So about half of our happiness is that inborn temperament. Then about 10%, she finds, is based on our current life circumstances. And then the last 40% is under our control. We can move the needle. We can make ourselves more likely to be happy by building a life that includes the conditions that make for happiness.

Chapter 2: The Relationship Advantage

ROBERT WALDINGER: The questions that we might ask ourselves about our relationships are kind of simple. One is, do I have enough connection in my life? Or do I even have too much connection? If I’m a shyer person and don’t need as many people in my life, so do I have what I need?