Mark Mattson and Valter Longo eat only once a day during the week, going without any food 23 hours at a time. Wolfram Tetzlaff sits down to a meal only every other weekday. And James R. Mitchell has tried skipping food entirely for several days at a time, though he much prefers juice fasts.
Their wacky eating is not about weight loss. The four are studying the possible benefits of short-term fasting, and figure they should experience it themselves.