A scientist who studies whether cutting calories could help us live longer shares how he eats, exercises, and de-stresses

• Professor James White researches whether restricting our calories could help us live longer.
• He practices caloric restriction in his own life — in a safe and sustainable way.
• White shared how he does this, plus his other habits for a long, healthy life.

A scientist who studies whether restricting calories in a safe way could help us live longer shared how he eats, exercises, and de-stresses for longevity.

Restricting the number of calories we eat causes low-level stress in the body, which triggers certain processes that remove markers of aging from our DNA, James White, an assistant professor in medicine at Duke University, told Business Insider. This is thought to help our cells function efficiently as we age.

In one study, he and his team found that mice who ate 30 to 40% fewer calories than others lived 40% longer. That's the equivalent of a human living another 30 years, he said. But humans aren't mice, so such studies can provide a proof of concept for further research, rather results that can be applied to us.

A separate two-year study that White also worked on saw 220 healthy participants who didn't have obesity eat around 100 to 200 fewer calories per day than they typically would. Their cardiometabolic health improved, as did their pace of biological aging. This was measured using markers in the blood, such as the proportion of white blood cells and changes to genes.

However, there isn't sufficient evidence to prove that calorie restriction can help us live longer.

While the jury is out, instead of obsessing over how many calories he eats, White applies his research to his life by eating nutritious foods, which tend to be lower in calories. He also tries to focus on maintaining his exercise routine, because he tends to eat healthier when he feels like he's "eating for a purpose."

White shared the other lifestyle choices he's made in the hope of living longer.

Eating enough calories to maintain a 'healthy' weight

White doesn't think people need to reduce their calories by much to get the potential life-lengthening benefits, particularly older people who should prioritize maintaining muscle mass. Instead, he tries to keep what he considers a "healthy" weight, where he has optimal body composition, by not overeating.

"You have to find a baseline safe calorie consumption for your body, where you're not gaining weight. Then every once in a while, if you want to cut a couple hundred calories, that's fine," he said, citing a 2019 study published in the journal Lancet Diabetes & Endocrinology. It found that healthy, non-obese participants aged 21 to 50 who restricted their caloric intake by an average of 11.9% for two years were less likely to develop cardiometabolic conditions and had better blood pressure levels and insulin sensitivity.

"But you don't have to calorically restrict all the time for years," he said. "Even if you restrict by a small percent for just a few days a week, we still see health benefits in our research."

It's important to note that calorie-restricted diets are not safe for anyone who is under 18, pregnant, breastfeeding, or has a history of disordered eating, Katherine Gomez, a registered dietitian, previously told BI.

Cardio and strength training

Similarly, slightly increasing the amount of physical activity you do can have "huge benefits on health and longevity," White said.

He exercises five or six days a week, doing both cardiovascular and resistance exercises to maintain lean muscle, muscle function, and endurance. He lifts weights and goes on walks, jogs, or cycles for 45 minutes to an hour each session.

But "there's a lot of literature that says that exercising three times a week is very effective," he said. A 2023 meta-analysis of over 30 million people without pre-existing health conditions published in the British Journal of Sports Medicine found that just 11 minutes of exercise a day appeared to reduce participants' risks of dying from chronic diseases such as cancer and heart disease.

Eating lean protein and lots of vegetables

White generally focuses on the number of calories he eats, using calorie tracking apps on his phone, rather than what he's eating, but he prioritizes lean proteins, vegetables, and healthy fats.

He also tries to limit carbohydrates, especially processed ones, because they're easier to overeat.

The Mediterranean diet, which follows similar principles, was voted the healthiest way to eat for the eighth year in a row by the US News & World Report. It's high in vegetables, fruit, whole grains, and legumes, and low in processed foods and added sugars.

Reducing stress by sleeping more

"It's very easy to get roped into a schedule of working all the time, getting little sleep, and just feeling overall stressed," White said.

So he tries to prioritize getting eight hours of sleep, which helps him destress, he said.

"Stress is inevitable, but sleep is a great way to reset," he said. "Sleep and stress are a constant work in progress that you just have to be mindful about and listen to your body."

BI previously reported on how a doctor who specializes in anti-aging reduces his stress levels every morning.