A recent study suggests a possible connection between weight loss drugs and hair loss. Specifically, individuals using GLP-1 agonist medications—like Mounjaro, Ozempic, and Wegovy—have reported hair loss to health officials, and data from around 50,000 participants appears to back this claim.
GLP-1s primarily aim to help manage diabetes and obesity by mimicking hormones that regulate blood sugar and suppress appetite.
Researchers compared the incidence of alopecia among adults taking GLP-1 drugs for diabetes against those taking alternative medications. The University of Pennsylvania Health System highlighted that U.S. regulators have been made aware of the hair loss reports related to semaglutide (found in Wegovy and Ozempic) and tirzepatide (Mounjaro).
In 2026 alone, the UK Medicines and Healthcare products Regulatory Agency (MHRA) received 399 hair loss reports for tirzepatide, and 541 from the previous year. There were also 148 reports for semaglutide, alongside 164 from last year.
The new research specifically looked at individuals with type 2 diabetes on GLP-1 receptor agonists versus those on SGLT-2 inhibitors or DPP-4 inhibitors.
Notably, the study compared 12,004 patients on GLP-1s to 15,221 using SGLT-2 inhibitors, and another 11,964 GLP-1 users against 11,233 DPP-4 inhibitor users. After accounting for various factors like age and weight, the results indicated that GLP-1 users had a 37% greater likelihood of experiencing alopecia than those on SGLT-2 inhibitors and a 68% higher risk compared to DPP-4 users.
Additional analysis linked hair loss specifically to non-scarring alopecia, a type where hair follicles remain intact, enabling potential regrowth.
The researchers shared their findings in the British Medical Journal (BMJ), noting previous reports and analyses from the FDA’s Adverse Event Reporting System have linked hair loss to the initiation of GLP-1 receptor agonists, notably semaglutide and tirzepatide. The FDA is assessing this safety signal.
While hair loss generally isn’t physically harmful, it could have considerable psychological implications, impacting self-esteem and quality of life, as well as treatment adherence.
Regarding the mechanism behind the hair loss, the researchers suggested it may stem from weight loss and reduced calorie intake, though they emphasize that further studies are needed. They indicated that calorie restriction may induce physiological stress and lead to deficiencies in vital nutrients like iron, zinc, and biotin, which are crucial for hair growth.
Other potential influences could be the metabolic, hormonal, and immunological effects of GLP-1 receptor agonists, which might affect hair follicle growth and cycling. For instance, they noted how these drugs have been linked to changes in thyroid function, and how delayed gastric emptying could impact the absorption of orally taken medications, including thyroid hormone treatments.
The research team concluded that their findings bolster previous anecdotal reports and offer more detailed evidence for clinical awareness of this adverse effect.
Additionally, recent reports indicate that these drugs may also contribute to a decline in the number of alcohol-dependent individuals being hospitalized, suggesting they might help reduce alcohol consumption. However, researchers in the U.S. caution that the supporting evidence is still limited and somewhat mixed.
