4 simple ways to eat for longevity in the new year, according to a Harvard nutrition expert

1. Eat more whole foods

"Well, first of all, focus on whole and minimally processed foods, especially plant foods," says Hu. Aim to incorporate more whole foods, like fruits, vegetables, whole grains, nuts and legumes into every meal, he adds.

Hu strongly recommends a diet similar to the Mediterranean diet, healthy plant-based diets or the Okinawan diet, which are all rich in whole foods.

"Those dietary patterns have been shown to reduce the risk of chronic disease like diabetes, cardiovascular disease, some cancers, and also the risk of dementia," he says.

"And because those are the major causes of death. That's why those healthy dietary patterns have been shown to reduce the risk of premature death and lead to longer life expectancies."

2. Reduce consumption of processed and ultra-processed foods

Once you've added more whole foods in your diet, Hu suggests cutting back on processed and ultra-processed foods.

"In the U.S. diet, almost 60% of the calories come from ultra-processed foods," including foods like soft drinks, snacks and sweets, he notes. "That's one of the reasons Americans consume too many unhealthy foods and too many calories."

A study that examined the health outcomes of more than 11,000 adults over the span of 19 years found that those who ate ultra-processed foods the most within that time frame had a 31% higher risk of all-cause mortality than people who ate ultra-processed foods the least.

"So, I think it's very important to minimize the consumption of those foods," Hu adds.

3. Be flexible with your diet

"There is no rigid type of diet that everyone should follow to live longer [and] healthier," Hu says. "I think there are different dietary patterns, and people can create their own fusion diet."

Identify which of the whole foods you really enjoy and make your own healthy diet, he says. You can mix and match the elements of a Mediterranean diet and an Okinawan diet, or create an entirely new diet altogether.

"That's how to actually improve their enjoyment and also long-term adherence to dietary patterns," Hu notes. It's important to "be more flexible and enjoy the healthy diet."

4. Use meal time for social gatherings

When it comes to longevity, lifestyle factors like physical activity, managing stress and diet are all extremely important. But there is yet another vital component to consider as well, and that's social connections.

Hu sees using meals as a time to gather socially as another way to maximize your chances of living longer.

"The connection between food and social connections is very natural, because food does bring people together," he says.

By prioritizing meal time as a moment for social gathering, you can simultaneously incorporate two behaviors that are linked to longevity, Hu says.

"Eating healthy food together, not only nourishes our bodies, but also nourishes our souls."

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