But scientists believe that the combination of foods in a predominantly plant-based diet may.

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"We all need to be moving towards a more plant-based diet, " Giancoli said.

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In addition, a plant-based diet loaded with at least two cups a day of a variety of produce is beneficial.

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He adopted a vegan or plant-based diet and six months later, with almost no experience, entered the extreme endurance event known as Ultraman.

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Researchers don't know why a plant-based diet seems to have a protective effect, but one likely reason is the nutrient profile of vegetarian diets, which tend to be higher in fiber and lower in saturated fat.

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