Wegovy and Mounjaro are used by millions of people for weight loss.
The best-known side effects include nausea, fatigue, and constipation, but researchers are now also investigating a possible link to hair loss, according to the Sun.
According to researchers at the University of Pennsylvania, rapid weight loss can lead to deficiencies in nutrients such as zinc and iron.
This may affect the hair's normal growth cycle, according to a study published in the British Medical Journal.
Also read: From teachers to drivers: The jobs linked to hidden health problems
More people have reported hair loss
UK health authorities consider hair loss to be a common or very common side effect of the treatment.
At the same time, the Medicines and Healthcare products Regulatory Agency in the UK has received 1,252 reports of hair loss from people who have used semaglutide or tirzepatide.
However, the researchers emphasize that rapid weight loss itself can also cause hair loss, even if it is not related to the medication. The condition is often temporary, and hair may grow back over time.
Study found a difference
The researchers compared around 24,000 people with type 2 diabetes who received either GLP-1 medication or alternative treatment.
Also read: Popular weight-loss drugs face new hair loss questions
The results showed that users of the weight-loss injections had up to a 68 percent higher risk of alopecia than those in the other group. The risk was highest among women.
According to the British Medical Journal, the study identified an association but does not prove that the medications are the direct cause of the hair loss.
Also read: New study finds drug reversed autism-like brain changes within hours