For centuries, humans have searched for the Fountain of Youth. The latest search for longevity may arrive in pill form. Scientists are now trying to extrapolate life-prolonging experiments in animals to something which would work on a human being. Two leading candidates are metformin—a common diabetes treatment—and rapamycin, a drug currently used to prevent transplant patients from rejecting organs. There is also a new class of drugs called senolytics. These clear the body of senescent cells, old cells that stop dividing but don’t die. They accumulate in tissues throughout the body and damage healthy cells and have been linked to cognitive impairment. Let’s hope at least one of these works!