April 18, 2026

6 min read

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Peptides promise longevity and healing. Does the science back them up?

The world of peptides has exploded in wellness circles, but the benefits of injecting these gray-market molecules rest on little clinical evidence

By Bethany Brookshire edited by Lauren J. Young

Tanja Ivanova/Getty Images

Want to speed up your recovery after an injury or a workout? Some influencers are fans of shots of BPC-157 and TB-500 for that. Want scar-free, youthful skin and thick hair? Reddit posts rave about GHK-Cu and KPV. Want to build beautiful, bulky biceps? Some fitness influencers swear shots of ipamorelin will do wonders. This is the world of peptides—an assortment of chemicals that promise to boost your body and health—and people are self-injecting them in a growing wellness trend.

Promoted by bodybuilders and influencers, supporters of the “Make America Healthy Again” movement and Silicon Valley early adopters, peptides promise results that leave people better than well, fitter than fit. Yet despite getting glowing reviews on social media, most peptides have limited clinical evidence to support health benefits, whether it’s helping to heal a rotator cuff injury, improving libido or building muscles. There’s not much information out there on the drugs’ effectiveness and even less on their safety.

In 2023 the Food and Drug Administration banned several peptides, including BPC-157, GHK-Cu, KPV and ipamorelin, from being produced in the U.S. by compounding pharmacies—facilities that legally make non-FDA-approved medications for individual use—because of “significant safety risks.” Many peptides are imported from outside of the country, and many made here are marketed for research use only. People who desperately want the promise contained in the tiny vials seek them out on online on legally dubious gray markets.

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But accessing the shots might soon get easier. On the podcast The Joe Rogan Experience on February 27, Robert F. Kennedy, Jr., secretary of the Department of Health and Human Services, proposed legalizing the compounding of 14 peptides—and the FDA seems poised to grant his wish. Earlier this week the agency released plans to hold a meeting with independent advisers in July to review whether some U.S. pharmacies should be allowed to manufacture certain peptides, including BPC-157, TB-500 and KPV.

If the lift on peptides happens, a flood of people could start using the drugs, regardless of any safety concerns.

A Peptide by Many Names

A peptide is a chain of two or more amino acids—building blocks of proteins. The body’s cells can produce numerous peptides, which perform various tasks or serve as signaling molecules.

Insulin is a peptide. So is human growth hormone—and semaglutide, the active ingredient in glucagonlike peptide 1 (GLP-1) receptor agonist drugs such as Ozempic and Wegovy. (GLP-1s are FDA-approved for managing type 2 diabetes and for weight loss). Buzzy new injections such as BPC-157 and GHK-Cu—touted for tissue repair—are derivations or synthetic versions of naturally occurring peptides. The public and online health retailers are starting to use “peptides” as a catchall term for any chemical taken for well-being, energy, exercise recovery, and more, says Luke Turnock, a criminologist who studies how people use enhancement drugs at the University of Lincoln in England.

And while people are using them as treatments, peptides aren’t often described as drugs. “‘Drug’ has a certain stigma or negative connotation attached to it,” Turnock says. The popularity of peptides has its roots in the bodybuilding and powerlifting communities, he explains, where “drug” has historically been tied to steroids—which are generally banned for professional athletes.

The term “peptides,” meanwhile, stresses the natural origin of the molecules, says Flynn McGuire, who studies sports medicine at the University of Utah. “Because it’s ‘natural,’ it is better or different, even though they’re just drugs,” McGuire says.

A Surge in Popularity

In the past few years, orthopedic surgeon Omar Rahman has seen a spike in interest in peptides. “I’m seeing more patients asking about peptides, often driven by the longevity and wellness space,” says Rahman, who practices at Pacific Coast Sports Medicine in Los Angeles.

Because peptides encompass many products—some available by prescription, others on the gray market—the exact number of people trying them is hard t