(Vienna, Austria, Thursday, 1 October 2026) Nail detachment is more than four times as common among people taking GLP-1 receptor agonists than among comparable people with obesity or type 2 diabetes who are not taking the drugs, according to the first controlled study to examine their potential effects on nail health.1
The multinational study, presented today at the European Academy of Dermatology and Venereology (EADV) Congress 2026, found that 39% of GLP-1 users reported nail detachment compared with 9% of controls, while two-thirds (66%) experienced at least one nail disorder.
GLP-1 receptor agonists are increasingly used to treat type 2 diabetes and obesity,2 but their potential effects on nail health have remained largely unexplored, with previous evidence limited to isolated adverse-event reports.
Researchers compared 575 GLP-1 receptor agonist users with 1,329 people with type 2 diabetes and/or obesity who had never taken the drugs, recruited across France, the United States, Brazil and Mexico.
Overall, 66% of GLP-1 users reported at least one nail disorder compared with 53% of controls. Beyond nail detachment, nail discolouration was also substantially more common among users, affecting 46% compared with 17% of controls.
Importantly, the increased prevalence of nail problems did not appear to be explained by weight loss alone. Differences between GLP-1 users and controls remained significant when researchers focused specifically on participants who had lost weight.
"Until now, nail changes associated with GLP-1 therapies had essentially been anecdotal," said study author Dr Charles Taïeb. "Our findings show a clear association, but they also underline an important point: not everything that happens during GLP-1 treatment is necessarily caused by the treatment itself."
The researchers caution that the study cannot establish that GLP-1 receptor agonists caused the nail changes. Around half of users reported experiencing nail problems before starting treatment, while adjusting for dermatological conditions and nutritional deficiencies reduced the strength of some associations. However, nail detachment and discolouration remained around two to three times more frequent among users after adjustment.
A companion study involving the same participants found that hair and scalp changes were also significantly more common among GLP-1 users.3
Unusual hair loss was reported by 50% of GLP-1 users compared with 34% of controls, while loss of hair volume or density affected 42% versus 19%. Hair loss beginning after treatment initiation was also more than twice as common among users (26% vs 12%), while scalp redness was around three times more frequent.
Importantly, hair loss among GLP-1 users rarely occurred in isolation, with the majority of cases accompanied by scalp symptoms such as itching, redness or scaling.
"This suggests that what is happening on the scalp may go beyond the classical shedding seen after rapid weight loss and involve an inflammatory component," explained study author Dr Bruno Halioua. "Scalp inflammation was the rule rather than the exception, which clinicians do not currently look for and which may be treatable. Taken together, our findings suggest that factors beyond weight loss alone may contribute to the hair, scalp and nail changes observed among GLP-1 users." For patients, Dr Halioua stressed that the findings should provide awareness rather than alarm.
"These changes are frequent, usually benign, and are not a reason to stop an effective treatment on one's own initiative," he said. "Anyone who notices hair shedding, an itchy or red scalp or nail changes should mention it to their doctor rather than discontinue therapy."
Both studies were cross-sectional and relied on patient-reported symptoms, meaning they can identify associations but cannot establish that GLP-1 treatment caused the changes. The researchers now plan prospective research following patients from the start of treatment, using standardised dermatological examinations and biological monitoring to establish when changes develop, why they occur and whether they are reversible.
