102-Year-Old Neurologist Shares His 6 Longevity Secrets: "You Need a Stimulus for the Brain"

1. Keep working for as long as it keeps you happy.

Tucker has some choice words when it comes to retirement, calling it "the enemy of longevity."

"You have to have some purpose in life and get up in the morning and know what you're about," he says. Speaking with Today, Tucker admitted that he doesn’t understand the fascination with "golfing three days a week," a common pastime among retirees.

However, he applauds non-working folks for taking up hobbies, especially ones that get them outdoors: "I’m going to caution [people]: If they retire from their work, they should at least do something as a hobby, whether it be communal work or self-hobbies…You need a stimulus for the brain daily."

2. Never stop learning.

Tucker knows a thing or two about perseverance. A 1947 graduate from The Ohio State University, he entered the medical field prior to the invention of MRI and CT imaging scans. He had to learn about computers and become well-versed with new hospital machinery throughout his decades-long career. While some of his peers viewed the challenge as too steep, Tucker embraced it.

"Don't say, 'I'm too old to learn this,'" he told Today. "You can't take that attitude."

In his early 60s, Tucker enrolled in law school for fun. He passed the Ohio Bar Exam at the age of 67. "Volunteering, pursuing a hobby, and learning new skills can provide great mental stimulation," he wrote in a CNBC article.

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3. Pick up a book.

"When I’m not reading about the latest advancements and treatments in neurology, I like to read biographies and detective stories," Tucker wrote in his CNBC piece. "Immersing yourself in a good book, fiction or non-fiction, requires your brain to process a bulk of new information. I believe this is key to keeping your mind sharp."

4. Find ways to move your body.

Workout routines evolve with age, but the important thing is that you’re finding ways to stay active, whether it’s daily neighborhood walks or joining a local pickleball league. In Tucker’s case, the centenarian kept up with swimming, jogging, hiking, and skiing into his late 80s.

His at-home gym is outfitted with a treadmill, a stationary bike, and a NordicTrack machine. "While I no longer ski and am not quite as active as I once was, I try to get in at least three miles on my treadmill at a brisk pace most days of the week. Watching Turner Classic Movies in the background helps curb some of the boredom," he wrote.

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5. Enjoy the foods you love in moderation (and don't smoke).

Though Tucker does recognize that "heredity and family history of longevity is a healthy start," as he told Today, he also believes that avoiding smoking and eating healthily most of the time are just as important, as is enjoying what you love in moderation.

"l have a martini and New York strip steak occasionally, but not every day," he wrote in another CNBC article. "Sara [his wife] is an excellent chef, and she’s helped me maintain a healthy and varied diet. We have salad with every meal, and enjoy greens like bok choy, broccoli and Brussels sprouts."

"The real secret to longevity is that there are no secrets. But we live daily and die once, so we must make the most of the time we have," he added.

6. Stay positive.

"You have to be happy in your job and in your domestic life," Tucker told Today. "Be happy in what you do, be loving to your friends and family, and just don't fret about the future. Life is short enough."

For Tucker, happiness means spending quality time with his wife of 70 years, as well as their four children and 10 grandchildren. He also doesn’t ruminate on death.

"I think I’ll live forever, knowing that it’s not real. But I feel that way. I never think of death," he added. "You die once, but you live daily…focus on the living."