• I interviewed some of the top longevity doctors in 2024: 3 things I learned from their approach to a long, healthy life

This year, I got in touch with several longevity experts to talk about living a long, healthy life — and to learn more about their own personal practices.

"Almost everything I recommend to my patients, I do myself," said Dr. Frank Lipman, a doctor of functional medicine who researches longevity.

Many of Lipman's suggestions for good health aligned with what I heard from Dr. Andrea Maier, a health and longevity expert with nearly 25 years of experience in geroscience, Valter Longo, who's been studying longevity in Italy for about 20 years, and the popular researcher Dan Buettner.

Here's what I learned from some of these leading experts in 2024.

3 things I learned from longevity experts in 2024

1. Most longevity experts follow time-restricted eating

In my conversations with doctors and researchers who study how to live longer, almost all seemed to recommend or follow time-restricted eating — commonly known as intermittent fasting. Most tend to eat all of their meals within an eight-hour window, and fast for about 12 to 16 hours a day.

"I always skip, or very often skip, breakfast," Maier said. "I really start eating at two o'clock [p.m.], three o'clock. Sometimes my first meal is in the evening, and I'm fine."

Longo developed his own meal pattern called the fasting-mimicking diet. It involves eating a diet "high in unsaturated fats and low in overall calories, protein and carbohydrates," according to the USC Leonard Davis School of Gerontology.

The diet also involves 12 hours of fasting daily, and was associated with a lower risk of developing diseases like diabetes, cancer and heart conditions in mice, according to a study published in the journal Nature Communications earlier this year.

2. They have cheat meals and non-negotiables

As serious as longevity experts are about their health, they still give themselves a bit of grace. That sometimes means enjoying things that aren't exactly the healthiest. They don't plan on changing those behaviors.

"I'm 46, and still drinking Diet Coke," Maier told CNBC Make It in October.

Similarly, Longo has a "big dinner, fairly late at night, and that's probably not ideal, but [it] makes my life much easier to have no lunch," he said. It would "probably be better to have a big lunch and a smaller dinner. [But] that's the way my life is set up."

Buettner, who helped coin the term "blue zones," enjoys going out for dinner with his friends and acknowledges that it likely doesn't align with a longevity diet.

"It's hard to eat really healthy when you go out, no matter where you go," Buettner said.

3. Connecting with others is really important to them

The importance of maintaining positive relationships was a common theme among longevity experts, and it mirrors what a decades-long Harvard study about happiness found about its significance for longevity.

For Lipman, spending quality time with his grandson is his current primary goal for social fitness. "When he gets older, he's probably not going to want to spend as much time, so I'm taking advantage. He's soon to be five, but he's still at an age where he wants to be around his grandparents."

And Buettner said he "overspent to buy a place where I can invite people," over and had three guests staying at his house at the time I interviewed him.

"I have every night planned with people, and that's when I get a lot of my social interactivity," he said.

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