Valter Longo

Valter Longo

The Fasting Evangelist

Longo, director of the Longevity Institute at the University of Southern California, believes that the secret to staving off the ills of old age is a diet designed to trick your body into thinking it’s fasting. He translated his years in the lab, researching the effects of fasting and calorie restriction, into a 2018 book called The Longevity Diet, which preaches a low-protein, plant-based eating style with regular periods of fasting. This diet, he claims, shifts the body’s metabolism and enhances the power of cells to help protect against chronic diseases like Type 2 diabetes and cardiovascular disease. Some small studies have found that a fasting-mimicking diet—the kind Longo ­advocates—helps people lose weight and body fat, lowers blood pressure and decreases levels of a hormone linked to aging and disease. Ideas like his are catching on: according to a 2018 survey from the International Food Information Council Foundation, intermittent fasting is this year’s most popular diet. Now, Longo is studying whether a fast-mimicking diet improves cancer ­outcomes—and can help prevent the disease in the first place. —Mandy Oaklander

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