If you’ve listened to The Drive With Peter Attia, Huberman Lab, or seen Andrew Huberman on Flagrant or The Joe Rogan Experience, or retained any of your chemistry curriculum, you’ve heard about peptides. Guys in pursuit of boosted one-rep-maxes, antiaging solutions, and increased muscle mass are conducting their own n=1 “studies,” often based on early research performed on mice or anecdotal evidence shared online. They’re looking to peptides, a confusingly wide-ranging group of compounds to acquire that edge. Antiaging clinics have popped up online, offering virtual consultations with doctors before shipping peptides to the user’s home, where they can self-administer them—often via injection. According to one doctor’s website, they can boost libido, provide sunless tans, address erection issues, and even treat Alzheimer’s. ”You name it, peptides do it,” it says.
Many of these peptides of interest, including BPC-157, ipamorelin, TB-500, and sermorelin, to name a few, are purported to affect growth hormone production, promote lean muscle mass, and melt off fat. One peptide, Melanotan, offers a way to develop tanner skin without stepping foot into the sun. (“Tanning pills” are not FDA approved, according to a statement the agency put out in 2022.)
There are peptides available to purportedly address hair health, problematic skin, aging, bone health, testosterone levels, libido, and obesity. A very broad range of compounds are technically peptides, from collagen to prescription drugs like Ozempic, which means saying you’re interested in taking a “peptide” is like saying you’re interested in consuming medicine. Except the peptides that biohacker types are most interested in can be purchased online and are largely untouched by the FDA.
It's an extremely broad category.
A peptide is a short chain of amino acids, which are the basic components that make up protein. Peptides are usually two to 50 amino acids connected by peptide bonds, which are strong bonds that can withstand heat, salt, and urea (a byproduct of protein metabolism) exposure. When ingested, these chains of amino acids can be broken down and used for energy. If the peptide is “bioactive,” it has a biological effect on the body beyond being used as a source of energy.
These short chains of amino acids are the topic of conversations across weight rooms, skin care newsletters, and biohacking forums for their wide range of potential uses. There are collagen peptides, which are marketed for purported benefits like improved hair health; joint-pain relief; and softer, younger-looking skin. You can find these at Costco, WholeFoods, and anywhere on the internet. There is BPC-157, the “Wolverine peptide,” given its purported effects on cellular regeneration.
The most important thing to remember, says Nick Milazzo, lead researcher at Examine.com, is “when someone says ‘peptides,’ it’s like saying ‘I’m taking supplements.’ Insulin is a peptide. There are a lot of things that fall in that category. Like most things, being specific is important, but being specific is also difficult.”
Peptides can have major, poorly-understood effects.
Even though you can access many peptides as easily as you can vitamins, they’re not the same. Vitamins are more like ingredients in cellular machinery, Milazzo explained, and especially with water-soluble vitamins, you simply pee out excess consumption.
Peptides that increase the production of growth hormone, on the other hand, have a large systemic effect, which has a potential effect and consequence, which should be done under medical supervision, as there are multiple biomarkers to track (via methods like blood and urine testing) to ensure safety.
One popular peptide that many people are looking into is Ipamorelin, which is a growth hormone secretagogue—meaning it encourages growth hormone production. All of these peptides are available for purchase, without a prescription, online. What’s more difficult to find is reliable human trials on any of them.
This popularity paired with uncertainty is part of the reason BPC-157 has earned coverage not just from podcasts, but the World Anti-Doping Agency, which added the peptide to The Prohibited List, joining Ipamorelin and numerous other peptides.
In explaining the addition, the United States Anti-Doping Agency (USADA) noted that BPC-157 is “not currently approved for use as a human drug,” but instead “has been investigated for inflammatory bowel disease and soft tissue healing, although there is a concerning lack of published clinical trial data because studies appear to have been cancelled or stopped without any published conclusions.”
But banning a substance only makes it more attractive to a certain kind of guy. That it is banned might be proof that BPC-157 is some real-deal shit, this guy’s thinking might go, but USADA’s rationale is more about what isn’t proven: “This substance is not approved for human clinical use by any global regulatory authority and it may lead to negative health effects,” says a statement on its website. In the same way that the Q-Tip box says “do not put in ear canal,” many online purveyors of peptides claim that their peptides are “not for human use.”
There are promising studies on peptides, says Milazzo. But many of them are very early, and focused on mice. Still, the term “peptide” sounds more advanced than vitamins and less sketchy than steroids. “People are thinking about this as like, Oh, is this basically an opportunity for me to get a drug, without me having to get a prescription or being expensive or having to go to a pharmacy,” he says. “Communications about peptides and media discussions of peptides definitely outpaces the research.”
The booming interest in peptides also highlights a broader problem with scientific research. “Ultimately, scientific journals are interested in putting out stuff that at least has the appearance of being important,” Milazzo says. Something like collagen-peptide research is “still young,” so the findings—both positive and negative—should be expected to be extreme.
Compounds like BPC-157, Milazzo says, are “closer to an experimental drug than something that would be considered a supplement.” The peptides that increase growth hormone production, like BPC-157 and Ipamorelin, might work, but carry serious health risks. When it comes to any peptides that affect growth hormone production, “I would professionally dissuade people from doing it,” Milazzo says. “Because you'd have to be prepared to risk your own health to consume the thing.”
The ability to create peptides has outpaced the time needed to test them for safety and efficacy.
Layne Norton, PhD, is a natural bodybuilder, IPF powerlifter, and a fervent debunker of weight room woo-woo. (He also recently squatted 617 pounds.) Norton attributes the booming interest in peptides to advancements in chemistry that allow researchers “to more easily mass-synthesize various compounds more easily.”
Technical progress in molecular modeling has also allowed scientists to rapidly determine which peptides are likely to have biological activity, and creating those compounds is now easier and faster than it has ever been before.
Norton is interested in peptides for their ability to possibly treat disease and be used as potential antiaging agents, he says. But “virtually all of them are overhyped at this point.” There are promising results popping up in petri dishes (in vitro studies) and in animal models, “but human data is very limited at this point.”
Norton says he’s cautiously optimistic about the true potential of peptides, but given that less than 50% of animal study findings carry over to humans, “these compounds really should be vigorously tested in human trials before being marketed to the public.”
The digestion process may make many of these peptides biologically inert, as digestive enzymes can break them down, though there are some measures that can be taken to protect them during this process. He’s also concerned about safety, as this space is “the Wild West” right now. Even if you decide to test out one of these bioactive peptides, he says there’s no guarantee the vial, pill, or spray you buy online actually contains that ingredient, or just that ingredient: “People should proceed cautiously before jumping on the bandwagon of untested or minimally tested compounds,” he says.