On an August morning, among the marble columns and Tuscan frescoes in the Fairmont Hotel’s Laurel Court restaurant, a back table became an impromptu chemistry class. Lynne Ji, a slim 27-year-old dressed in black athleisure, moved aside a china teapot, unzipped a black business-class airline pouch, and tipped an array of glass vials onto the table. They contained powdered and liquid versions of the peptide retatrutide, a next-generation GLP-1 compound made by pharma giant Eli Lilly, currently in Phase 3 clinical trials (opens in new tab). It was getting a lot of buzz in her group chats, she said.
Ji, a retired poker pro who dabbles in crypto, began microdosing retatrutide in February. Within days, she said, her “food noise” faded, her portions shrank, and her weight dropped from 135 to 115 pounds. “I am exactly vain enough to inject myself to look thinner,” she said. “I played poker for a career, so taking risks doesn’t bother me.”
Ji’s stash didn’t come from a pharmacy but from a Chinese peptide dealer she’d been connected to on WhatsApp by tech friends. She paid the guy $195 for 10 vials. “Three weeks later, it shows up at your door,” she said.
Ji’s approach to DIY dosing is part of a growing Bay Area trend that’s evolving beyond psychedelics and nootropics into needles and peptide stacks. This cohort of mostly tech industry people are injecting research-grade peptides in hopes of a health or performance boost to address everything from fat loss and recovery to focus and libido.
A few years ago, most people didn’t know a peptide from a protein shake. Then came Ozempic (opens in new tab), which turned GLP-1s (glucagon-like peptides, originally designed to treat diabetes but repurposed for weight loss) into a household name. Serena Williams shills GLP-1s for the telehealth brand Ro (opens in new tab), and SF-based telehealth company Hims & Hers advertises microdosing GLP-1s on Muni buses.
But GLP-1s, which mimic gut hormones to help regulate blood sugar, are only one branch of peptides, which are strings of amino acids that build proteins and act on certain cell types to change functions in the body. You’ll find peptides in luxury (opens in new tab) skincare serums and oral supplements, but doctors consider injection the gold standard for efficacy.
Enthusiasts stock up on peptides like BPC-157 (“body protection compound”) for tendon and ligament (opens in new tab) healing; GHK-Cu, a copper peptide believed to increase collagen (opens in new tab) and hair growth; Thymosin alpha-1 (opens in new tab)(TA-1) for immune support; Selank to reduce anxiety (opens in new tab); and Semax, developed for stroke (opens in new tab) recovery, for a brain boost. Some of these health claims are supported by small studies; others by little more than message-board testimonials. Regardless, for some DIY health experimenters, the term “peptide” has become synonymous with quick fixes and radical life upgrades.
That DIY culture is colliding with a regulatory crackdown.
Starting in 2023, the Food and Drug Administration began steadily restricting access to popular (opens in new tab) peptides, moving several — including BPC-157, CJC-1295, and ipamorelin, which were formerly available from U.S. compounding pharmacies — into its “Category 2 bucket (opens in new tab),” shorthand for bulk substances that “may present significant safety risks” like poor immune responses, and shouldn’t be compounded. (Some were removed from that list in 2024. (opens in new tab))
Robert F. Kennedy Jr., the Health and Human Services secretary, has tweeted complaints about the FDA’s war on peptides (opens in new tab). But that has not led to any change to regulations or availability.
Health hackers have turned to the gray market to source their vials from dealers in China, where most peptides are manufactured. These dealers sell vials labeled “not for human use.” Purchasing this way amounts to a regulatory hack that opens the Chinese supply chain to anyone with a credit card, under the fiction that the drugs are for laboratory use only. Chinese peptide imports from non-FDA registered companies rose 44% from December to January, according to the Partnership for Safe Medicines, a nonprofit watchdog. (opens in new tab)
Representatives for the FDA declined to comment but directed The Standard to the agency’s website (opens in new tab) Concerns with Unapproved GLP-1 Drugs Used for Weight Loss, which warns against purchasing peptides labeled “for research purposes.”
Despite peptides being one of pop culture’s buzziest words right now – alongside Labubu and matcha — they’re not a new phenomena. Peptides were discovered in humans in the 1920s, but it wasn’t until breakthrough synthesizing techniques were developed in the 1950s that scientists began studying their use in treating disease.
Thousands have been cataloged, and around 100 peptide-based drugs have made it to market, with 150 in active clinical trials. “Peptides are super important,” said pathology professor Katrin J. Svensson, who runs a metabolic regulation lab (opens in new tab) at Stanford University. “They often have fewer side effects than other types of drugs.” Since peptides are already present in the body, adding more is considered low risk, she added..
Research-grade peptides usually arrive as powders that require dilution with bacteriostatic water. But what shows up in the mail is anyone’s guess. “There is no regulation on the purity,” said Svensson. “It’s pretty dangerous.” Risks range from accidental overdose due to inconsistent labelling to vomiting and severe dehydration, or even sepsis, “if mixed in unsterile conditions,” she said.
Even the first step, mixing, can be dicey, Svennsson warned; the math behind the dilution process, referred to as reconstitution, is complex enough to spawn countless online “peptide calculators.” Eyeballing a vial isn’t enough. “Holding the bottle up to the light doesn’t mean it’s actually dissolved,” she said. “You need an instrument to determine this.”
Tim Fitzgerald, who runs the Human Optimization Center (opens in new tab), a wellness spa in Walnut Creek offering cryotherapy, red-light therapy, and other treatments, began using peptides in 2016 after suffering a herniated disc and autoimmune issues he attributed to “vaccine injuries.” Within weeks, his pain was gone, he claims. He emphasizes lifestyle changes — “protein, training, sleep, light — all of it matters” — alongside “use as needed” peptide injections.
“It’s not a magic bullet,” he said. “Someone who’s a metabolic dumpster fire isn’t going to get the result just by hopping on a shot.” He has cycled through a few types of peptides; treating a condition called “small intestine bacterial overgrowth,” (SIBO), a concussion, and muscle healing. Recently, though, he took a break: “I was starting to feel a bit like a human pin cushion.”
The Peptide bros
Max Marchione, the baby-faced 25-year-old cofounder of Superpower, a telehealth-for-longevity startup based in SoMa, isn’t fazed by the needles.
Before the company moved offices in September, the communal fridge doubled as a pharmacy. Mornings began with a ritual: Marchione lifting his shirt to swab his abs, cofounder Jacob Peters dropping trou to swab his butt, and Shaun Miller, the vice president of medical operations, alternating between hip and backside. (“I didn’t know people injected anywhere else,” said Peters.)
Marchione started with peptides a few months ago but is already an evangelist. “All that matters is if I increase performance, even if it introduces a bit of short-term risk,” he reasoned, focusing on improvements in sleep, muscle gain, cognition, and immunity. “If that improves performance, it justifies it long term.” What hooked him was the contrast with supplements, which he could swallow daily and still feel no shift in energy, focus, or recovery.
As none of his preferred peptides are approved by the FDA, Marchione buys products labeled “for research use only.”
“I get them from a Chinese peptide dealer,” he said. He’d prefer to source them domestically. “When you make something that people want hard to get, you create a black market,” said Miller. “The sentiment went from ‘I have my favorite compounding pharmacy’ to ‘I have my Chinese peptide dealer.’ If the supply wasn’t restricted, people would still be going the legitimate path.”
Miller’s $1,000-a-month peptide stack is small change next to Peters’ $5,000 (“It’s a lot of money, but it’s such a massive ROI,” said Peters.) and Miller’s $2,000. (Biohackers have a nickname for Miller’s four daily injections: the “Wolverine Stack.”) Marchione’s stack includes two shots in the morning and one at night, with others on an ad hoc basis.
As the hype over peptide efficacy outruns the data, Marchione has become an unexpected source of info for the community. His phone pings at all hours with sourcing and dosing questions from founders and investors. While The Standard watched, he pulled up a photo of a New York friend’s freezer jammed with tiny, color-capped vials. “That’s probably $100,000 to $250,000 worth of peptides,” he said. “Maybe more, in retail value. You gotta get on the peptide train.”
Hence the emergence of Superpower’s Peptide Friday. In June, the company began doling out syringes alongside coffee at its weekly all-hands breakfast for the 20 to 30 employees who work in the office. The lineup has included thymosin alpha-1 (often dubbed by fans as an “immune booster”) and NAD, a coenzyme known for supporting cellular repair. “It started as a joke,” said Marchione. But the company’s roughly 150 employees are into the free peptide shots, said VP of operations Adam Small, noting that it’s a good way to get more folks to come into the office to work.
Many purchasers of gray-market Chinese peptides have complained about the wildly varying quality. This infuriated Michael Carter, the San Francisco-based founder of Play.co (opens in new tab), a mobile gaming startup. After he re-injured his back in 2024, friends suggested peptides. He felt a lot better but hated buying from a sketchy website. “I don’t want to inject some crazy thing,” he said. “You’re opting out of the FDA, but you don’t want to opt out of supply chain safety.”
In March, he launched Finnrick, (opens in new tab) a peptide-testing platform backed by AngelList founder Naval Ravikant; Cameron Teitelman of StartX, Stanford University’s innovation accelerator; and Walter Kortschak, a venture capitalist and early investor in Lyft, Robinhood, and Palantir. “I made the investment in the belief this is a rapidly growing market,” said Kortschak. “Having more transparency [provides] great benefits to everyone.” Consumers mail in their vials, and the samples get sent to labs for free testing (similar labs charge fees) (opens in new tab) of purity, quantity, and potency. Finnrick also buys batches itself, taking steps to conceal its identity from the sellers. For each sample, the verdict comes back — a grade of A through E, with A the best — and is published online. Paid subscribers get extra analysis.
Finnrick has tested 2,378 samples (with another 1,500 in the queue) of 15 types of peptides from 122 vendors. The lab found zero semaglutide in five of the six vials tested from one vendor, and the sixth had 5% extra product, which could lead to accidental overdosing (earning that company an E grade).
“We get emails from vendors demanding we take the data down,” said Carter. He doesn’t. The project doesn’t make unapproved drugs safe, but it makes the risk more legible. “Everyone has a peptide guy,” he said. “What people need is transparent information so they can make their own decisions.”
Not everyone is sourcing their peptides themselves. Some concierge doctors offer non-FDA-approved peptides via overseas channels, domestic “research use only” sellers, or via the small number of compounding pharmacies allowed to serve licensed clinicians.
“I’m only as good as my compounder,” said Dr. Bronwyn Holmes, a San Francisco specialist in anti-aging and pediatrics who sits on the medical advisory board at Eden Health, a telehealth platform. Holmes has prescribed peptides since 2018, often BPC-157 and thymosin for women recovering from cosmetic surgery and GLP-1s for weight loss. Around 20% of her weight-loss patients are on retatrutide, the investigational peptide. “I see an uptick in, ‘Hey, I saw this on a podcast. What do you think?’” she said.
Dr. Molly Maloof (opens in new tab), a Bay Area physician who has lectured at Stanford University and specializes in treating tech executives, is all in on mainstreaming peptides. “I’m bullish, because I believe peptides are medicine for health and not just disease,” she said. “We’re going to see a lot of the gray market become the white market in the next decade.”
Maloof has a proactive approach to peptides: “I don’t recommend anything to patients I haven’t tested myself,” she said, describing four daily injections. The standout has been Selank, an anti-anxiety peptide, (opens in new tab) designed to calm the nervous system without sedation while potentially boosting focus and memory.
“My god. You definitely notice a major shift — your brain just feels smooth,” she said. “It’s so nice.” To source quality peptides, Maloof visits labs, verifies supply chains, and pushes chemists for proof via batch numbers, test methods, and results.
But Maloof and Holmes are concierge doctors with concierge pricing. For people without sufficient money or connections, the fallback is usually a sketchy website they heard about on a podcast. A thirtysomething San Francisco-based engineer told me they flew to Mexico for injections “from a witch.” Another sourced a dealer via Telegram.
Ji, the retired poker player, doesn’t pretend peptides are risk-free. “I’m almost certain this is not a miracle drug that has zero long-term damage,” she said of microdosed retatrutide. She has also tried semaglutide and BPC-157. She worries friends are taking unnecessarily high doses. But for the most part, the curiosity outpaces the concern.
“Under 20% of my friends do it,” she said. A higher number have pulled the trigger on peptide purchases, but not on the syringe. “They mentally put it on hold. They don’t really care, as they’re in pretty good shape. But they’re curious, so …”
So now they have a peptide guy, too.