He's a fan of calorie restriction, I can tell you that. He's also a fan of the keto diet. His business partner in the biotech company they are building together took it one step further and is a keto-vegan (she has a Ph.D. in the same subject as him). He does one "cheat" day a week, where he can eat anything he wants to, though, or his strict diet would be too cumbersome for him. His business partner never cheats. She has a ton of willpower. I've been vegan since 1993, before anyone else I knew was doing it, so with a couple of Ph.D.'s following me into that lifestyle, I feel like a trendsetter. :)