TV host Andy Cohen spent the summer doing it. Actor Rebel Wilson’s making ads about it. Sports Illustrated swimsuit model Brooks Nader says she’s “addicted” to it. The “it” in all three instances: “microdosing” a GLP-1 weight loss medication.

This concept – using very small amounts of the popular and pricey drugs, less than the FDA-approved minimums – seems to be everywhere, suddenly. Countless telehealth platforms have begun to offer it, with varying angles. One such company, Found, ran a full-page ad in The New York Times that said, “Microdosing GLP-1s isn’t cosmetic. It’s clinical.” Their website promises help with food cravings as well as improved mental clarity, sleep, heart and blood sugar health, and hormonal balance.

“Our program is clinically defined for patients with early metabolic dysfunction where lower doses may be most effective for prevention of progression to overt disease,” Found Senior Medical Advisor Rekha Kumar, MD, said in a statement. “This is medical intervention for documented metabolic risk – not cosmetic weight loss for otherwise healthy individuals.”

Seeing microdosing everywhere might make you think that a lot of research proves this method works. But it’s just the opposite. As promising as it appears, especially for certain health conditions, nearly all the evidence is anecdotal at this point – based more on personal experience than science. Kumar’s statement went on to acknowledge the unofficial nature of the approach: “Clinicians routinely apply established research through clinical judgment. That’s what we’re doing here, with appropriate evaluation and monitoring.”

Doctors can legally prescribe medications for off-label use – treatments that appear to work but haven’t received FDA approval. But it’s illegal for drug companies to advertise those options. Which means telehealth companies are mining a gray area. “They’re advertising some of the real benefits of GLPs, but claiming that subtherapeutic dosing is going to still offer those same benefits,” said Jennifer Manne-Goehler, MD, a researcher at Brigham and Women’s Hospital in Boston who’s done research on the effects of GLP-1 medications. “And I don’t necessarily think there’s any evidence for that.”

One of the scientists who first experimented with GLP-1 medications in the 1980s, Daniel Drucker, MD, explained it even more bluntly. “Simply put, there is no clinical trial data supporting microdosing. We have anecdotes and testable hypotheses but no meaningful data,” he wrote in an email.

It’s easy to see why people might want to try these plans: They’re much less expensive than brand-name GLP-1s, which cost about$500 each month without insurance, direct from the drugmakers. Telehealth options for microdosing hover around $200 a month. Plus, with very low doses, side effects may be less pronounced.