I’ve studied longevity for 35 years: Here’s the 1 habit I won’t change even for a longer life

But even Longo, who hopes to live to 120, knows that it’s important to consider “what people can change and what people cannot change,” including himself.

Here’s one thing that Longo says he isn’t planning on changing, even if it could increase his chances of living longer.

After decades of research, Longo concludes that “diet is by far the most important” factor for longevity.

While he eats foods that align with a Mediterranean diet, which studies suggest may reduce chances of developing heart disease and Type 2 diabetes, Longo says having all of your meals within a certain time frame each day is also important.

“I recommended 12 hours of fasting daily. Let’s say you eat between 8 a.m. and 8 p.m. [or] 7 a.m. [and] 7 p.m.,” he says. This eating pattern is called the fasting-mimicking diet.

Additionally, the old adage of “breakfast like a king, lunch like a prince, dinner like a pauper” is also backed by science for leading to better health outcomes and closely aligns with the diets of the world’s longest-living people.

But having smaller portions for dinner at an earlier time isn’t something Longo does, and it wouldn’t be ideal for his schedule.

“I have a fairly big dinner, fairly late at night, and that’s probably not ideal, but [it] makes my life much easier to have no lunch,” says Longo, who is also the director of the Longevity Institute of the Leonard Davis School of Gerontology at the University of Southern California-Los Angeles.

“I don’t have lunch Monday through Friday, and then I have a big dinner,” he adds. Longo understands that it would “probably be better to have a big lunch and a smaller dinner. [But] that’s the way my life is set up.”

In the grand scheme of things, he believes the negative effects of eating a large dinner at later times in the day are relatively small.

“That’s one of the compromises that I live with,” Longo says.

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