“Do you remember that term ‘experimental jab’?”
Dr. Adrian Chavez is sitting in his Austin home, a city many health contrarians and wellness influencers recently fled to in search of “medical freedom.” Armed with a PhD in nutrition, he’s spent years pushing back on medical misinformation on social media. I nod, well aware of the so-called renegade doctors wrongly applying the phrase to mRNA-based COVID vaccines.
“There’s no better way to describe peptides than that derogatory term that was used during COVID.”
We laugh at the irony: some of the same people claiming COVID vaccines weren’t properly tested (they were) are injecting themselves with peptides, which they say are well-tested (they’re not). Peptides are chains of amino acids, thousands of which naturally occur in our bodies and serve important functions, like fighting disease and aiding in muscle recovery. Synthetic peptides, artificial versions of our natural ones, have been used therapeutically for a century—insulin launched the field of peptide therapeutics in 1921. Some of these peptides, like insulin and now GLP-1 weight loss drugs are incredibly well tested, studied and scrutinized by researchers before making their way safely to consumers via the pharmaceutical industry. Other peptides, like human growth hormone, have boomed among the bodybuilding crowd—which still heavily traffics in peptides—and have been circulating the wellness grey market for years in off-label and potentially unsafe capacities.
Now, wellness influencers have gotten a hold of peptides and marketed them to treat and heal everything imaginable. Online, people are buying untested injectable peptides that promise all kinds of purported benefits, from weight loss to better sleep to better athletic performance. Influencers are hawking these substances in “stacks,” or combinations of potentially unsafe injections that claim to better your health, but really might contain totally unknown substances. In Chavez’s view, these are the real experimental jabs.
“Is peptide stacking the future of personalized medicine?” That’s how chiropractor Will Cole frames peptide therapy. His sales funnel leads to his Functional Peptide Program, a $97/month service marketed as “the only peptide therapy program built on a functional medicine foundation.”
As with many wellness influencers, Cole employs science-sounding jargon to market his products. His doctorate is in chiropractic; the other listed credential is Doctor of Natural Medicine. Cole’s website stipulates that he does “not practice medicine and do[es] not diagnose or treat diseases or medical conditions.” That hasn’t stopped Cole from capitalizing on the peptide trend. His online shop also sells peptides.
While influencers like Cole market peptides for “system-wide balance,” their first mainstream off-label use was strictly for performance enhancement. In 1989, a new doping class, peptide hormones and analogues, was introduced by the International Olympic Committee (IOC). Since then, dozens of peptides like Human Growth Hormone (hGH) and Adrenocorticotropic Hormone (ACTH) have been banned in competitions. Wellness influencers have greatly expanded on their perceived benefits. Cole for one promises increased energy, improved recovery, reduced inflammation, and better cognitive function. In one post, Cole lists five popular peptides. Two of them—creatine and spermidine—aren’t actually peptides. (Playboy reached out to Cole for comment but has not yet heard back.)
Numerous influencers like Cole, emboldened by RFK Jr.’s Make America Healthy Again (MAHA) movement, hawk peptides to optimize health and improve longevity—two phrases currently in vogue. MAHA-adjacent influencer Gary Brecka sells them for metabolic optimization, recovery, and cellular resilience. Brigham Buhler, founder of Ways2Well, offers clinician-supervised peptide therapy. The program is said to “transform your health with professionally supervised peptides designed for weight loss, lean muscle, faster recovery, sexual health and peak performance.” While peptides have shown clinically efficacy in weight loss and sexual health, the other claims are all speculative. Unsurprisingly, neither man has a medical degree.
Jordan Feigenbaum does, however. The strength coach and competitive powerlifter received his Doctor of Medicine in 2016. He’s watched colleagues peptide stack (injecting multiple peptides for a perceived synergistic effect) for over 20 years. While some have gone through early-phase human trials, most have not, and virtually none have been studied for the specific purposes many bodybuilders use them. The most hyped among them, BPC-157, has essentially no credible human evidence. Joe Rogan extolled its benefits back in 2022.
“People are viewing this like a supplement stack,” Feigenbaum says. “You take protein, creatine, and a pre-workout. They’re extending that same logic to peptides, under the auspices that these aren’t drugs. They think the risks can’t be that bad because they’re natural. And I predict bad stuff is going to happen. DIY pharmacology seems like an incredibly risky endeavor.”
Risky but enticing given the financial incentives. The global peptide therapeutics market reached nearly $50 billion in 2025 and is expected to surpass $100 billion by 2034. That’s just for approved peptide pharmaceuticals like GLP-1s and cancer treatments. An entire gray market trades countless peptide drugs by exploiting regulatory loopholes, raising significant safety concerns.
In 2023, the FDA moved a number of peptide raw material substances to the Category 2 Bulk Drug Substance list. Compounding pharmacies were no longer able to manufacture a variety of peptides. The agency cited insufficient human safety data, the potential for immune reactions, and impurity concerns.
One study found that semaglutide products sourced from gray market sellers ranged between 7-14% pure despite being advertised as 99%. Another study found purity levels as low as 5%, as well as batches contaminated with arsenic and lead. Meanwhile, RFK Jr has claimed that peptides are being suppressed and recently said he’s “very anxious” to put 14 of the 17 banned peptides back into circulation.
Ironically, the FDA’s crackdown may have exacerbated the purity crisis by driving consumers toward unregulated Chinese manufacturers. American compounding pharmacies exploit an FDA loophole that lets them sell peptides “for research only,” meaning don’t put it in your body, wink wink. These three words shield gray market peptides manufacturers of liability.
Banned substances presented as research chemicals are actually quite hard to research. Dr. Rachele Pojednic works as Stanford Lifestyle Medicine’s Director of Education and Chief Science Officer of Restore. She’s interested in the efficacy of peptides. Like any good researcher, she wants proof they actually work. Yet researching peptides is nearly impossible given their current designation.
“Even if I wanted to study these peptides, I can’t because they can’t be compounded in the United States, which means we don’t have a reliable supply chain,” she says. “If we don’t have a reliable supply chain, I can’t get an IRB [Institutional Review Board]. I can’t get ethics approval. Yet you can go on Google or into longevity clinics and they’ll give you a prescription or send it to you in an unmarked label.”
Despite these concerns, wellness fans continue to inject untested chemicals into their bodies while refusing one of the most tested anti-aging protocols in existence— a vaccine. And while they raise red flags about the tested and safe childhood vaccination schedule, they’re fine “stacking” peptides, even when experts worry about the untold consequences.
“We don’t understand how manipulating these compounds in our body might impact various cellular processes in the liver or kidneys,” Chavez says. “There could be damage occurring in different organ systems from the actual peptides themselves because they haven’t been well-studied in humans.”
Feigenbaum says stacking always runs the risk of terrible consequences. “You don’t know how they’re going to interact, which is why it’s important to have robust clinical data showing potential risks and drug side effects. We also want to see their efficacy. In bodybuilding, people love their growth hormone despite effectively all evidence showing not-so-great effects as far as actual gains in skeletal muscle tissue and improvements in strength.”
The wellness market recommending peptides is part of an anti-expert legacy that’s long favored alternative medicine. Today’s influencers prey on valid frustrations with our manically for-profit, patchwork healthcare system that bankrupts hundreds of thousands of Americans every year. The MAHA movement rose to power in part due to honest frustrations citizens have with this system. So far, Kennedy’s time in office has included slashing research funding, firing experts, spreading fear of vaccines, and rewarding the wellness market. He announced his intention to remove peptides from the banned list on Rogan’s podcast, where he said they’ve worked for him. Anecdote as proof of efficacy.
It’s not to say that peptides don’t hold genuine therapeutic promise—we’ve seen how well some of them work with GLP-1s. But Kennedy’s HHS, busy firing researchers who could confirm efficacy and safety, is ensuring we won’t find out anytime soon.