Rapamycin is immunosuppressive drug used to help treat some cancers. It's also used in kidney transplants to help the an organ recipient's body accept new kidneys, Insider reported.
The pill can slow down cellular growth and reproduction which means it might be a way for "aging bodies turn down troublesome age-related inflammation" which can contribute to age-related diseases like cancer and Alzheimer's, Insider reported.
Insider reported that researchers have already seen rapamycin slow aging in flies, crustaceans, yeast, mice. In humans, studies have shown that it may help improve immune function, especially in older adults, Insider said.
Despite its potential to be a "fountain of youth" no one has really nailed down the right way to regulate the drug for aging, Insider said.
Matt Kaeberlein, a longevity researcher studying rapamycin's effects on humans, previously told Insider "the doses that people are taking off-label are all over the place," adding that, "it's the wild west."