While vigorous exercise and healthy diets are tried-and-true ways to extend one's lifespan, in recent years, people have turned to prescription drugs with the hope of living a longer, healthier life.

One such drug is rapamycin, a pill that is typically prescribed to patients ahead of organ transplants "to bring the immune system down," according to Dr. Andrea Maier, a longevity expert and internal medicine specialist.

Popular advocates for anti-aging like Dr. Peter Attia swear by rapamycin and its longevity effects — he has been taking the pill for years.

But of the use of off-label rapamycin for longevity, Maier says: "[it] might have potential, beneficial effects for the aging body of humans. However, we don't have much knowledge yet."

So, how did the drug get the attention of people like Attia in the first place?

A 2014 study showed that rapamycin extended the lifespan of mice by more than 20%. It's also been found to extend the lifespan of fruit flies and worms, but first caught the attention of researchers when it extended the lifespan of yeast.

Certain users of the drug claim it has aided in weight loss, reduced body aches and led to the growth of dark hair that had already gone gray, according to The New York Times. But there isn't much research to support its effectiveness or its safety for long-term use in humans.

"My group is doing trials with rapamycin to see if we can lower the biological age of middle-aged individuals to prevent age-related diseases later in life," Maier says.

There are bigger, more robust clinical trials that are examining the effects of rapamycin on human longevity by investigating if the drug can affect certain diseases that are prevalent in aging adults, like Alzheimer's.

For people who are taking rapamycin for purposes other than what has been approved by the FDA and who are not participating in a clinical trial, "I would be very cautious, because it's a very potent drug. It can [cause] many side effects. It is hugely influencing the immune system," Maier says.

Suppressing your immune system has risks like making you more vulnerable to infection. Research also shows that rapamycin has caused nausea and mouth sores in some people, as well as high cholesterol, The New York Times reported.

"We don't have the drug or the supplement yet [that] everybody should take. Absolutely not," Maier says.

"I think it's very unlikely that we will ever have a drug everybody should take."

Maier recommends taking up simple and safe practices for longevity like brain tests to keep your mind sharp, prioritizing social fitness by spending quality time with loved ones and eating a nutrient-dense diet.

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