Study links popular weight-loss drugs to increased male hair loss

Men already at risk genetically for the most common form of hair loss have a 7 percent added risk of losing their hair if they use drugs like Ozempic, Wegovy, and Zepbound for type 2 diabetes and obesity, a new study shows.

Led by researchers at NYU Langone Health, the study focused on the GLP1R gene, which naturally increases the body's levels of glucagon-like peptide-1 (GLP-1) receptor proteins, and used it as an indicator of GLP-1 agonist activity. More GLP1R activity means there are more GLP-1 receptor proteins. The researchers compared the presence of GLP1R genes with the presence of genes found in men with androgenetic alopecia, an inherited form of hair loss that follows a pattern along the top and front of the scalp. Male hair loss conditions are well studied, unlike hair loss in women, which is why the researchers could only analyze any causal link to hair loss in men.

Many GLP-1 users, both men and women, have reported thinning hair as a side effect, with researchers so far attributing the shedding to the rapid weight loss driven by the medications, which work to regulate blood sugar and suppress appetite. Often, GLP-1 users have found that hair growth resumes several months after their weight stabilizes. Until now, researchers have only suspected a genetic connection between GLP-1 use and hair loss.

Publishing in the Journal of Investigative Dermatology online Sept. 3, the study showed that the GLP1R genes that naturally cause higher levels of GLP-1 receptor proteins are more likely to be present in men who have androgenetic alopecia. The researchers then adjusted their analysis to discount for known risks of hair loss from hypertension, which is thought to reduce blood flow to the scalp, harming hair follicle growth. The 7 percent added risk remained the same.

Researchers also checked their risk analysis against other potential drivers of hair loss, including insulin resistance (a cause of type 2 diabetes) and lowered testosterone levels. Still, the increased risk of hair loss from GLP-1 use remained at 7 percent.

Because the study involved genes active in both GLP-1 users and men with hair loss, any overlapping risk, the researchers noted, suggests that the two are biologically linked.

Our study provides the first genetic link between GLP-1 use and an increased risk of male- pattern hair loss from androgenetic alopecia, an association long suspected but until now not shown scientifically." 

Lynn Petukhova, PhD, study senior investigator, assistant professor in the Ronald O. Perelman Department of Dermatology and the Department of Population Health, NYU Grossman School of Medicine

"Our findings suggest that, if future experiments prove successful, some men, and possibly women too, could be screened and benchmarked for their risk of hair loss before being prescribed GLP-1 medications," said Dr. Petukhova. "We could also envision these findings leading to some GLP-1 users being prescribed combination treatments to prevent hair loss, such as minoxidil or some other drug."

Dr. Petukhova said further research is needed to understand the biological mechanisms that cause GLP-1 use to weaken hair follicle growth. She also has plans to investigate whether the links seen in men apply to women.

For the study, researchers accessed large, publicly available genetic databases, including the eQTLGen database of 31,684 mostly White men and women, and the Complex Traits Genetics group database of 205,327 mostly White men.

Androgenetic alopecia is estimated to affect half of White American males over age 50, and almost the same number of White American females over age 50, predominantly those who are postmenopause.

An estimated 12 percent of Americans have used GLP-1 drugs for no other reason than weight loss, including one-fifth of women ages 50 to 64, according to surveys. Since the first GLP-1 drug (Ozempic) was approved by the Food and Drug Administration in 2020, prescriptions for the medication have more than tripled.

Funding support for this study was provided by National Institutes of Health grants R01AR080796 and K01AR075111.

Besides Dr. Petukhova, NYU Langone researchers involved in the study were co-investigators Jerry Shapiro, MD, and Kristen Lo Sicco, MD. Other study co-investigators were Derek Mass, MBA; Mary Casagrande, MPH; and Poppy Gould, PhD; and co-lead investigator Archie Spindler.

Drs. Shapiro and Lo Sicco have in the past served as study investigators for hair loss drugs and devices manufactured by Pfizer and Regen Labs. Dr. Lo Sicco is a paid consultant for Pfizer, Lilly, Ro, Priovant, Veradermics, and Aquis. The terms and conditions of all these relationships are being managed in accordance with the policies of NYU Langone.

Additional study authors are co-lead investigator Ravi Ramesur, MD, PhD, at the University of Pennsylvania and King's College London, and co-investigator Atlas Khan, PhD, at Columbia University.