About a year ago, Dan started biohacking. The 44 year-old Australian exercises, tries to eat "pretty healthy," tracks his sleep with a fitness ring, meditates, and tests his blood regularly, all in the name of staying fit and well as he gets older.
And, once a week, Dan pops a few milligrams of rapamycin in his mouth. It's an immunosuppressive drug that is typically taken daily to help treat some cancers, or encourage organ recipients' bodies to accept new kidneys. But Dan's started taking a little bit every week, in the hopes of helping his body stay young.
His family, he says, thinks he's "crazy" for taking off-label rapamycin, but he says he just didn't want to wait until he's old and sick to play pharmaceutical "whack-a-mole" with his body.
Dan asked that Insider not publish his last name because he's not prescribed all of the drugs he takes to combat aging by licensed doctors. Instead, he gets some of his pills on the internet, through foreign pharmacies. He takes the cheap diabetes drug metformin daily,and pops several $1-2 rapamycin pills at the end of each week.
Aging experts say it's possible that Dan's rapamycin may be the closest thing we have found to a fountain of youth so far. Some biohackers, researchers, and doctors have already decided to try rapamycin out on themselves and on their patients, in the hopes that they may be able to avoid more chronic diseases, pain, and suffering as they age. But they're not sure yet if it actually works — and if it does, at what cost.
Rapamycin tells cells to stop growing
Rapamycin, also known as sirolimus, was first discovered in a clump of dirt on the island of Rapa Nui. This natural antifungal restricts a key protein in our body that is critical for helping cells grow and reproduce.
Like fasting, rapamycin tells cells to slow down their growth and reproduction.
While that kind of activity could be very dangerous for a growing fetus or young person, it may also be a great way for aging bodies to turn down troublesome age-related inflammation that can contribute to conditions including Alzheimer's disease and cancer.
Rapamycin keeps flies and mice young — but we don't know if it can do the same for humans
In lab studies, rapamycin has helped flies, crustaceans, yeast, and mice all live longer, healthier lives. In mice, rapamycin has delayed age-related issues including tumors, cognitive decline, and cardiovascular problems. It's being tested in healthy, aging dogs across the US now.
Studies of rapamycin that have been done in people already suggest it can improve immune function in older adults. Rapamycin has been shown to boost how elders respond to flu shots, and lowered their odds of getting severely ill during cold and flu season.
Matt Kaeberlein, the director of the Healthy Aging and Longevity Research Institute at the University of Washington, is studying how more than 330 rapamycin users averaging around 60 years old report feeling while taking the drug off-label. His main goal is to ensure their ad hoc self-prescribing methods are safe. But, it's been hard for him to tell, given all the differing protocols.
"The doses that people are taking off-label are all over the place," Kaeberlein said. "It's the wild west."
No one has figured out how to take Rapamycin for aging
No one knows the best dosage or timing for taking rapamycin to stave off aging. But some suggest the drug is arguably safer and more precise than metformin, another off-label aging fix popular with biohackers. Side effects of metformin can include explosive diarrhea and painful stomach cramps, but the main side effect of rapamycin Kaeberlein has noted in his study is canker sores, in some patients' mouths. He's also noticed some "interesting" signs that the drug may be acting as an antidepressant or anti-anxiety medication in some patients. He even tried out rapamycin on himself, to deal with a frozen shoulder.
The potential for long-term toxicity with rapamycin is another open question scientists are discussing. Lab studies in rats and mice suggest it's possible that taking rapamycin indefinitely could mess with the pancreas and encourage insulin resistance, the classic diabetes precursor.
Scientists aren't yet sure that rapamycin can do for humans what it has done for mice and other animals. But many are hopeful, since beneficial effects on aging bodies are seen across such a wide range of other organisms.
"We have cured cancer in a mouse 50 million times – and it doesn't translate to a human," Dr. Joan Mannick, who has studied how rapamycin affects older adults' immune systems, said on a recent episode of the "Longevity by Design" podcast, expressing cautious optimism about the drug.
"I think we're going to crack this one and we'll figure it out, but people should wait 'til it's cracked," she said.
