Jane, a software developer from the Bay Area, flew to the Bahamas in October and dropped around $30,000 to have donor stem cells injected into her hip joints. A self-proclaimed pickleball fanatic, she was desperate to stop early-onset osteoarthritis from benching her at 42.

“She’s a little young to get a hip replacement,” said Dr. Rowan Paul, the Bay Area sports medicine and orthopedic physician who traveled to the Bahamas to treat her. The hope was that stem cells from healthy donor bone marrow processed by a Swedish biotech company would regenerate damaged joint cartilage and reduce inflammation.

 “Stem cells were considered fringe, [but] they’re now in the public consciousness,” Paul said, noting that in the Bay Area there are many “early adopters.” 

This procedure could not happen legally in the U.S. The Food and Drug Administration allows the use of donor stem cells only to treat cancers or immune disorders (with exceptions for research), due to documented risks of blindness, tumor formation, and bacterial infections.

But other countries and territories, like Panama and the Cayman Islands, have more relaxed policies, which has led to a boom in  stem-cell-seeking luxury tourism.

Perhaps the most high-profile stem-cell tourist is none other than the man running the Health and Human Services Department that oversees the FDA: Robert Kennedy Jr. In a recent podcast appearance, the HHS secretary revealed that he had traveled to Antigua to get stem cells injected in his throat.

“Why did I have to go to Antigua?” he wondered aloud.  

The answer is that a cottage industry of international stem-cell luxury clinics, operated by licensed doctors from the U.S., has cropped up to serve rich Americans seeking experimental treatments. These clinics carry stem cells sourced from compliant labs that adhere to international regulatory standards, and one-percenters are increasingly willing to travel long distances and pay extremely high sums to get them.

Stem cells, known as the body’s building blocks, form and repair tissues and organs. Scientists agree that they have vast potential to treat disease. Adult mesenchymal stem cells, or MSCs, have the ability to differentiate into  certain cell types, whereas embryonic stem cells are like blank Scrabble tiles, capable of becoming almost any cell in the body.

“They have huge regenerative properties,” said Dr. Deepak Srivastava, president of Gladstone Institutes, a nonprofit life science research organization. “It’s incredibly exciting.” But “true stem cells” are available only via clinical trials, he added, and scientists and doctors are only just beginning to understand their therapeutic applications.

Stem-cell use took off in the 1950s with bone marrow transplants for leukemia, despite risks like cancer and rejection. Advances in the 1970s and ’80s expanded use cases, and by the 2000s, stem cells had been embraced in sports medicine for their anti-inflammatory and healing effects, an alternative to the tissue damage associated with corticosteroids.

But as hype outpaced oversight, a $2.4 billion global market emerged for unregulated stem-cell treatments. It’s a money grab for “desperate people,” said Srivastava. “They’re marketing stem-cell therapies without any evidence.” 

Medical tourism is not a new phenomenon; people have long flown abroad for cheap surgeries and sketchy procedures like rib removals. What’s different about stem-cell tourism is that it targets the elite, who hope it will help with everything from aging to fertility, pain management, and bone and skin problems — despite mixed clinical evidence of its efficacy.

“The agency is aware of Americans traveling abroad to receive unapproved stem-cell therapies,” an FDA spokesperson said, noting that its researchers “do not track adverse effects.”

The luxe clinics where the wealthy get injected are worlds apart from the budget stem-cell centers dotted across China, India, and Latin America that purportedly treat everything from autism to erectile dysfunction. Many of these bargain clinics operate in a regulatory black box and have reportedly resulted in complications like leprosy bacterial infections in Mexico and tumors in Argentina. Over the few days that Paul was in the Bahamas last fall, he treated Jane and nine other patients, each of whom had paid anywhere from $30,000 to $60,000 as part of a patient-funded clinical trial — meaning it had research protocols, standardized dosing, and ongoing monitoring to track long-term outcomes.

 “The reality is we don’t know [if it will] benefit people, but we start with a clinical trial and see how people do,” said Paul.

Since 2012, Paul has injected patients — San Francisco 49ers, ballet dancers, and numerous tech execs — with their own bone-marrow stem cells in his Bay Area clinics. This is legal, but in the US he is limited by how much he can extract. 

This led him to seek out Physical Longevity, a consortium of orthopedic specialists partnering with Cellcolabs to run self-funded MSC clinical trials in the Bahamas, like the one Jane was part of, where the rules are different.

Influencers in the sports and tech world have fueled public interest in stem-cell treatments. Last year, George Kittle, the tight end for the San Francisco 49ers, credited umbilical cord stem cells he’d received in Panama with healing his injured Achilles tendon. “I haven’t had an issue since,” he said. “Give stem cells a chance. Taking a risk on something you might not know about is worth it.” His teammate Kyle Juszczyk  is a regular at the same Panama clinic.

In 2024, Bryan Johnson, the “Don’t Die” guru, traveled to the Bahamas to have 300 million MSCs injected into his knees, shoulders, and hips to treat injuries. He paid $25,000 as part of Cellcolabs patient-funded clinical trial, which included an MRI and musculoskeletal ultrasound. 

There are no conclusive studies that stem cells speed up recovery for athletic injuries. But doctors think that for healthy people, the risks are low. “The main risk is infection or that they don’t work,” said Dr. Jordan Shlain, founder of Private Medical in Marin.

But with or without evidence, there’s nothing the ultra-wealthy love more than borrowing from the health-optimizing playbooks of elite athletes. For Peter Fioretti, 65, longevity co-chair at R360, a private network for centimillionaires, stem-cell therapies are one of many protocols he and his peers use, including therapeutic plasma exchanges and annual MRIs. “We’re always discussing what has legitimacy and what’s snake oil,” he said of longevity treatments. “And we have access to scientists and doctors researching it.”

In 2023, Fioretti flew to a Costa Rica stem-cell clinic that had been recommended by members and vetted by his doctors. Millions of stem cells were injected into his knees, but the improvement was minimal, he said; a slight boost in workout recovery time and surprisingly “sharper vision.” His ophthalmologist said his retinas are now similar to those of a 30-year-old, rather than an “old man,” he recalled. 

“Some members spend several hundred thousand a year focusing on staying young for as long as possible,” he said. “This stuff is experimental.”

Bay Area concierge doctors say patients increasingly have been asking about stem-cell therapies. Dr.Abe Malkin, founder of Concierge MD, said his team sometimes facilitates travel to Mexico or Costa Rica for patients seeking donor stem cells. “If they’re going anyway, I’d rather they go somewhere reputable,” he said.

But not all doctors who cater to longevity-focused clients are onboard with stem-cell travel. Joanna Zhu, senior director of the Human Longevity clinic, said company policy is to discourage patients from seeking stem cells and steer them toward data-driven preventative care. “We think stem cells are the next step, but we don’t do stem cells here,” she said.

Beyond general longevity and sports performance, many Bay Area women are hoping stem cells can reverse infertility. Dozens have traveled to the Bahamas for ovarian or uterine stem-cell injections, paying $6,500 to $15,000 per trip, with multiple sessions suggested.

“It’s a shot in the dark,” said Marin-based fertility specialist Dr. Aimee Eyvazzadeh, who reported that a small number of her patients had seen improved egg follicle counts after stem-cell treatment. “I haven’t seen any complications.”

But complications from stem-cell injections are not uncommon. And many of the claims about the benefits are overstated or flat-out wrong.

“No one’s being intellectually honest about the probability that it won’t work … as there’s so much money to be made,” said Shlain, who has seen what happens when stem-cell treatments go wrong. A 58-year-old tech mogul received 200 million stem cells in November at an unnamed San Francisco clinic. The next day, his heart rate spiked, and he called Shlain. The patient had a history of supraventricular tachycardia but had not had episodes in the previous eight years, said Shlain, who monitored him closely. 

Two days later, the patient developed malignant hypertension, a severe rise in blood pressure that required emergency care, which Shlain attributed to overstimulation from the stem cells. The clinic denied responsibility. 

In another case, one of Shlain’s patients developed a spinal abscess from a stem-cell injection at an outside clinic. “He got this rare bacteria,” said Shlain, noting that it required major surgery; the issue wasn’t the stem cells but an infection at the site. He’s furious with these clinics. 

There are around 2,754 unlicensed U.S. stem-cell clinics, where treatments have been linked to blindness, infections, and even death. Oversight is minimal; in 2024, the FDA sent a total of 13 warning letters. “It’s probably safe to say no more crackdown with the new administration,” said Paul Knoepfler, a professor of cell biology and human anatomy at UC Davis who tracks questionable stem-cell treatments. 

If a person wants to get donor stem cells without traveling internationally or going to a sketchy clinic, there are ways to make this happen — but they’re not recommended.

A senior researcher at a well-known Bay Area futurist institute said she received stem-cell knee injections in a hotel room at San Francisco International Airport, and she feels great. Srivastava, president of Gladstone Institutes, was appalled when he heard this. “The baseline for treatment should be a sterile hospital setting,” he said.

The smart move for the stem-cell curious is to wait, he said.

The wait won’t necessarily be long. The first approvals for stem-cell treatments, sought in the 2010s, are just now coming through, said Karl Pfleger, founder of Aging Biotech, which tracks the clinical-trial pipeline. In 2024, the first mesenchymal stem cell therapy was greenlit for children. More are coming.

“Diabetes, vision loss, epilepsy, spina bifida … we’re going to see more approved therapies in the next 5 to 7 years, probably sooner,” said Knoepfler. “The pipeline of legit stem-cell therapies is more promising than ever.”

Srivastava highlighted a Phase 1 stem-cell trial for patients with Type 1 diabetes, which found that most no longer needed insulin after treatment. If replicated, the treatment could be fast-tracked and available within five years.

Longevity treatments that address aging-related frailty, muscle loss, and back pain are not far behind. 

And if Kennedy gets his way, the process may speed up even more. At an FDA roundtable this month, the HHS secretary pledged to accelerate approvals, telling scientists, “We want to make sure we are getting rid of the regulatory impediments that stop you.”

As for Jane, she’s back on the pickleball court.