A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.

Dr. Michael Rozien mostly eats a Mediterranean diet.Cleveland Clinic/Getty Images Dr. Michael Roizen is 78, but says his "biological age" is 57.6.He's the chief wellness officer at … [+4016 chars]

A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.

A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.

A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.

A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.

A 78-year-old doctor says he's reversed his age by 20 years. Here are the 4 diet principles he follows to stay young.