CATEGORY: HEALTHY AGING & LONGEVITY
Biologists at UC Berkeley set out to answer a blunt question: does semaglutide, the drug sold as Ozempic and Wegovy, do anything about aging itself? In mice, the answer was yes. Elderly female mice given daily semaglutide lived to a median of 834 days, against 742 days for untreated mice, a gap of roughly three months on a lifespan of about two years.1 They also kept sharper memories and steadier balance. This is an animal result. Nobody has shown anything like it in people.
Treatment Began at the Mouse Equivalent of Old Age
This wasn’t a human study at all, but a controlled laboratory experiment published in the journal Nature. Researchers took mice that were already 20 months old, well into mouse retirement, and split them into two groups: 40 received a daily injection of semaglutide and 39 received saline, with the treatment continuing for the rest of their lives. Separate groups of treated and untreated mice went through three months of testing on memory mazes, balance, grip, and treadmill endurance. All of the animals were female. The team says that choice was practical, since male mice housed together fight and injure each other, but it means the study can’t say whether males would benefit at all.
Longer Lives, and Better Ones
The treated mice didn’t just last longer. They found their way through a spatial memory maze more reliably, stayed on a rotating rod longer, ran farther on a treadmill, and handled blood sugar better than untreated animals of the same age. Under the microscope, their tissues showed less inflammation, less DNA damage, and more newborn neurons in the brain’s memory hub. The researchers also pitted the drug against the one intervention that has slowed aging in animals over and over: simply feeding them less. Semaglutide matched that approach on most measures and beat it on memory and blood sugar handling, which suggests the drug isn’t only mimicking a smaller appetite. Something else may be going on, and the authors say finding that pathway is the next job.
What a Mouse Can and Can’t Tell You
Millions of people already take semaglutide for diabetes or weight, so it’s tempting to read this as a bonus they’re quietly collecting. The study doesn’t show that. It covers one drug, one dose, one strain of mouse, and one sex, and no laboratory has yet repeated it. Mice have the same GLP-1 receptor the drug targets, the lock its key fits, yet plenty of treatments that stretched mouse lifespans have gone nowhere in humans. The authors are plain about this: only long-term clinical trials could show whether semaglutide changes how people age. What the result does do is put a widely used, well-studied medicine on the short list of serious candidates for human aging research, and that list has never been long.
Key Takeaways
- Female mice started on daily semaglutide at 20 months old lived a median of 834 days, versus 742 days untreated, roughly three extra months.
- Treated mice also held onto memory, balance, endurance, and blood sugar control that untreated mice lost.
- The drug matched a reduced-feeding comparison on most aging measures and outdid it on memory and glucose handling, hinting at effects beyond appetite.
- This is a single study in female mice only. No human study has tested semaglutide against aging, and the authors say long-term trials would be needed.
References
- Feng Y, Barthez M, Wang Y, et al. Late-life semaglutide treatment slows ageing and extends lifespan in female mice. Nature. 2026;657(8131):469–476. link