With the popularity of GLP-1s skyrocketing, the “P,” which stands for peptides, is having its own moment.
Peptides are naturally occurring chains of amino acids that send signals to our bodies to perform important processes. They regulate the immune system, grow cells, reduce inflammation, manage hormones and more.
Bodybuilders trying to boost their muscle mass and biohackers seeking to optimize their health and longevity have used synthetic peptides for years. But in the last several months, unregulated peptides have burst into the mainstream, largely through social media.
Investigating journalist Ezra Marcus said once he heard the buzz around peptides, he started looking into them for a New York Magazine article. He even tried two injectable peptides, one from a medical spa in New York and one purchased directly from a Chinese factory online.
The nurse at the med spa prescribed him a six-week supply of NAD+, a compound that reportedly boosts focus and energy. Then, Marcus went online to purchase a six-month supply of a GLP-1 called Retatrutide that was developed by Eli Lilly but not approved by the Food and Drug Administration.
”These peptide forums on Reddit are obsessed with it and are buying it bootleg from China,” Marcus said, “so I figured I would do the same thing that they’ve all been doing and try taking it.”
8 questions with Ezra Marcus
What did you hear from people you interviewed about why they started taking peptides?
“A lot of people that I talked to started taking it themselves because of just the sense that people around them — whether it was at the gym or people they knew from school or people that they knew from just their social life — were getting ahead, were getting these amazing outcomes, were looking younger, were fitter, were losing weight. And there was a sense of trying to keep up.”
Some of these peptides, like insulin or GLP-1s, are approved by the FDA. But you reported that the global peptide market has now swelled to more than $50 billion in annual sales, and is projected to nearly double again in roughly the next decade.
How are influencers promoting and driving sales of these peptides?
“ You have these extremely popular GLP-1s that are driving a lot of interest in exploring this sort of injectable medication. You’ve now primed people to believe in these as a sort of miracle cure, because everyone sees how effective the GLP-1s are.
“Then there’s all these other somewhat less regulated — I mean, significantly less regulated — compounds that are quite easy to obtain. They have not been tested. They’re not FDA-approved, but they’re easy enough for somebody to buy from a factory in China and set up a storefront on the internet and hire an influencer to make a video talking about the amazing outcomes that you’re going to get and start selling these things.”
You bought peptides online from one of these Chinese factories. How did that work?
“ I joined a Discord that I found from Reddit of peptide enthusiasts. In the Discord, there was a sales representative for a Chinese factory, and I spoke with the representative who sent me a menu of dozens of different peptides. I sent $150 in Bitcoin and received a six-month supply in the mail two weeks later of a GLP-1 called Retatrutide.”
Did anyone ask you to talk to a doctor? Did anybody ask you to provide a medical report?
“Certainly nobody asked me for any of the above. This is totally outside of any kind of health care system or any kind of safety protocol.
“There is a sort of ad hoc, DIY version of people trying to make sure that they’re getting the right thing, which is that this community of peptide enthusiasts are repeatedly buying from this one person and talking to each other and saying like, ‘Look, I got the right thing. It gave me X, Y, and Z effect. I had it tested independently.’”
How is it legal for these factories to package up and send you drugs to America that have not even been FDA-approved?
”Well, depending on the drug, it’s not legal. I mean, in many cases, they are bootlegging drugs that have patent protections, and basically, they’re playing whack-a-mole with the pharmaceutical companies when they’re making bootleg Ozempic or Retatrutide, those are patent-protected compounds. So they’re essentially just playing a numbers game.
“When you go through the process of buying them on the websites, they’ll all say, ‘This is for research purposes only.’ That’s a sort of fig leaf they’re using to be able to sell these things that are obviously not for research purposes. They’re for people to inject.”
What side effects did you hear about from people taking unregulated peptides?
“ If you’re not testing it, it’s not uncommon for the dosages to be totally wrong. They might tell you that you’ve gotten five milligrams of X, Y, and Z, but really, it’s 15 milligrams. So if you’ve got a totally different amount of what you think you’re taking, that could be quite dangerous, especially to take too much of something.
“Furthermore, I mean, these haven’t been studied, and I talked to people who had ranging from moderate to severe side effects from taking various peptides, ranging from gallstones to just nerve pain, kidney stones.”
In your article, you talked with someone who got acute necrotizing pancreatitis. What does that mean?
“ That was someone who was taking an extensive dose of Retatrutide, of a GLP-1, to lose weight for a bodybuilding competition, and essentially his pancreas failed.”
Since 2020, the FDA has worked to restrict peptides that they say carry significant safety risks. However, Health Secretary Robert F. Kennedy Jr. has vowed to end what he called the FDA’s war on peptides.
At a time when we’re seeing more interest in peptides, do you think we’re also going to see correspondingly less regulation and consumer protection?
“ I think so. I think that RFK and the [Make America Healthy Again] movement see peptides as part of a suite of compounds that, as they see it, have been kind of improperly restricted by the pharmaceutical industry. And they want to essentially remove the restrictions the FDA put in place that have kept compounding pharmacies, sort of independent pharmacies, from making these drugs.”
This interview was edited for clarity.
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Grace Griffin produced and edited this interview for broadcast with Michael Scotto. Griffin also produced it for the web.
This article was originally published on WBUR.org.
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