The fountain of youth may be filled with grapefruit and human sperm, according to Austrian researchers, according to Newser. The scientists found that spermidine, a chemical compound abundant in both sperm and grapefruit, increased longevity by around a third in fruit flies and worms when it was added to their diet. Human immune cells also lived longer when cultured in the compound. The spermidine slowed the aging process by making cellular processes more efficient, according to researchers.

"Clearly we have to do a lot more research to discover if it can have a direct effect on aging in humans," the lead researcher told Chemistry World. "What is interesting is that spermidine is a natural compound which probably has no side effects. People could try to stay young by eating a lot of grapefruit and having a lot of sex. It might not work but I don`t think it would do much harm."