how to live to 100

In 1909, [John D. Rockefeller's] doctor predicted that he would live to be a hundred because he followed three simple rules: "First, he avoids all worry. Second, he takes plenty of exercise in the open air. Third, he gets up from the table a little hungry."

Some unexpectedly elegant advice from The Prize by Daniel Yergin.

(Rockefeller's doctor wasn't too far off.)