My 3 rules for a long, happy life are simple

Howard Tucker died on Dec. 22, 2025 at age 103, shortly after writing this story for CNBC Make It. It is published here with the permission of his family.

I spent over 75 years working as a neurologist, until my hospital closed in 2022. Now, at 103 years old – and recently named the oldest doctor ever by Guinness World Records – people often ask how I stay happy, sharp and fulfilled.

I don’t believe there is one magic answer. Good genes and luck can certainly give you a head start. But over the years, I have come to believe that there are a few very important principles.

These are my three non-negotiables for a long and meaningful life – they’re simple, and almost anyone can follow them.

I tell all my patients that the mind is like any other muscle in the body: If you don’t use it, it gets weaker.

My work keeps me thinking, learning and solving interesting problems. When one chapter of my medical career ended, I found another way to continue with legal review and learning to use social media. I don’t want an excuse to quit.

In my early 60s, I went to law school at night after working full-time as a doctor. I passed the Ohio Bar Exam at age 67. I didn’t set out to break the record. I did it because law, like medicine, interests me and I have always believed that it is important to continue learning.

A job does not have to mean a job or a job. It could mean volunteering, reading, learning a skill, playing music, joining a club or finding any activity that keeps your mind active.

I have seen many people slow down when they stop connecting with the world. In my experience, staying mentally active is one of the best things you can do for yourself.

When people ask me about my longevity, most want to know about my secret diet or exercise. Diet and exercise are important, of course. But I also think your perspective on life is important.

I have been around for a long time. Like everyone else, I experience disappointment, loss and injustice. But I don’t think it makes sense to carry hatred around me.

Anger and resentment take over. They take the burden physically. In my opinion, they do more damage to the person carrying them than anyone else. Anger can raise your blood pressure, increase stress hormones and increase your risk of heart disease over time. Not to mention the mental energy wasted on hating someone.

You don’t have to forget all the wrongs or make excuses for bad behavior. The point is not to let anger rule your life. I have always felt that it is healthy to move forward, to stay interested in other people, and to focus your energy on the things that make life meaningful.

I don’t believe that living well means depriving yourself of all pleasure.

I enjoy a martini. I enjoy a good steak. My wife of 68 years, Sue, is a wonderful cook, and we always eat well. We also believe in moderation, lots of salad, vegetables and moderation in everything.

For me, moderation is what makes happiness happen over time. Be sensible about what you eat. It is the same in many areas of life. Too much of anything can deplete you. Very little can do the same.

So the best advice I can give is to keep your mind active, stop being angry and enjoy life. Each day is an opportunity to live well, so why not make the most of it?

Dr. Howard Tucker was a neurologist from Cleveland, Ohio. He was named as “Oldest Doctor Ever” by Guinness World Records at 103 years old. Throughout this illness, he taught medical residents and treated patients at St. Vincent Charity Medical Center, and law students at Case Western Reserve University. He also starred in the feature documentary, “What’s Next?“, produced by his grandson, Austin Tucker, and directed and produced by Taylor Taglianetti.

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