A new study in The BMJ found that people with type 2 diabetes taking GLP-1 medications like Ozempic and Wegovy had a higher risk of non-scarring alopecia compared to those taking other diabetes drugs. The research from Penn Medicine showed a 37% higher risk versus SGLT-2 inhibitors and a 68% higher…
A large-scale study published in The BMJ has identified a potential link between the use of GLP-1 medications, including Ozempic and Wegovy, and an increased risk of hair loss in adults with type 2 diabetes. The research compared the incidence of alopecia among individuals taking GLP-1 drugs with those using two other classes of diabetes medications: SGLT-2 inhibitors and DPP-4 inhibitors. Specifically, the study found a higher risk of non-scarring alopecia, a typically temporary or reversible form of hair loss that includes conditions such as telogen effluvium and androgenetic alopecia.
The findings are based on electronic health record data from the University of Pennsylvania Health System Penn Medicine covering the period from January 2019 to September 2024. The researchers analyzed data from two separate cohorts. In the first cohort, they examined records from 12,004 GLP-1 users and 15,221 SGLT-2 inhibitor users. In the second cohort, they compared 11,964 GLP-1 users with 11,238 DPP-4 inhibitor users. The results showed that compared with adults taking SGLT-2 inhibitors, those on GLP-1 medications had a 37% higher chance of experiencing hair loss. When compared with DPP-4 inhibitor users, GLP-1 users had a 68% higher risk of hair loss.
It is important to note that these findings do not establish the risk of hair loss in people taking GLP-1s for non-diabetes purposes, such as weight loss alone. The absolute risk remains low, with approximately six or seven out of every 1,000 people taking GLP-1 medications experiencing hair loss each year, according to data cited in the study paper. The researchers emphasize that while the absolute risk is low, understanding the potential for alopecia can help patients weigh the benefits and risks of their treatment options and make informed decisions.
The observational study drew on electronic health records from Penn Medicine over nearly six years, from January 2019 to September 2024. The large sample sizes in both cohorts provided statistical power to detect differences in alopecia incidence. In the GLP-1 versus SGLT2i cohort, 12,004 GLP-1 users were compared with 15,221 SGLT-2 inhibitor users. In the GLP-1 versus DPP4i cohort, 11,964 GLP-1 users were compared with 11,238 DPP-4 inhibitor users. The study focused on clinically recorded non-scarring alopecia, a type of hair loss that does not permanently damage hair follicles.
The elevated risk was significant: GLP-1 users had a 37% higher risk than those taking SGLT-2 inhibitors and a 68% higher risk than those taking DPP-4 inhibitors. These figures come from the study published in The BMJ. The researchers noted that because this is an observational study, it cannot confirm a direct cause-and-effect relationship. It cannot determine definitively that weight loss or nutritional deficiencies led to the hair loss, but the study authors did point to a possible association.
Mir Ali, MD, a bariatric surgeon and medical director of the MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, commented on the findings. Ali, who was not involved in the study, said that the increased risk compared with SGLT-2 inhibitors 37% and DPP-4 inhibitors 68% is notable but not entirely surprising given that significant weight loss by any means can result in hair loss. He added that the medication acts as a catalyst for weight loss, but the resulting physiological stress and hormonal changes are often the direct trigger for telogen effluvium.
The study suggests that rapid weight loss, a common effect of GLP-1 medications, may be a key factor behind the hair loss. Telogen effluvium is already associated with weight loss, and the rapid weight loss experienced by some GLP-1 users could lead to non-scarring alopecia. Additionally, calorie restriction while taking these drugs may lead to nutritional deficiencies that affect hair growth. The study authors identified deficiencies in biotin, iron, and zinc as possible contributors to hair loss.
Other factors may also play a role. Changes in thyroid function and altered absorption of oral medications, such as thyroid hormone or sex hormone drugs, due to delayed gastric emptying caused by GLP-1s, could contribute to hair loss. These aspects were noted in the study paper as potential mechanisms.
Mir Ali recommended that patients maintain adequate protein intake and supplement appropriately with key micronutrients, especially iron, zinc, and biotin, while on these medications. He advised that routine monitoring should include checking basic nutritional labs if hair loss becomes a concern.
Experts not involved in the study offered additional insights. Manish Mittal, MD, a hair transplant surgeon at Mittal Hair Clinic, explained that the vast majority of patients will never experience clinically significant hair loss. He noted that the study reinforces that shedding can occur in a small proportion of people and is something clinicians should discuss before treatment. Mittal emphasized that groups more at risk include those with pre-existing nutritional deficiencies, those experiencing very rapid and significant weight loss, women with low iron stores, individuals recovering from bariatric surgery, or those with underlying androgenetic hair loss. These individuals may notice shedding more readily because they already have reduced hair reserve.
Opel Baker, MBChB, DipOccMed, MRCGP, a general practitioner at the Mayfield Clinic in Brighton, United Kingdom, also commented. Baker advised that the most important thing is not to panic and not to discontinue treatment without medical advice. Patients should aim to lose weight at a sustainable pace rather than as quickly as possible, prioritize adequate protein intake, and attend regular follow-up appointments. If hair shedding develops, Baker recommended assessing dietary intake and, where clinically indicated, arranging blood tests to check for iron deficiency, thyroid disease, vitamin B12, or other contributing factors. Monitoring is straightforward and can form part of routine reviews.
Mir Ali further emphasized that for the vast majority of patients seeking treatment for obesity or diabetes, the metabolic benefits of GLP-1s significantly outweigh the risk of temporary, non-scarring hair loss, which usually resolves once weight stabilizes. He reiterated that groups more at risk are those with pre-existing nutritional deficiencies or those experiencing very rapid, significant weight loss.
Working closely with a healthcare professional is crucial for managing hair loss or monitoring for changes when taking GLP-1 medications. Patients should not stop treatment because they are worried about hair loss alone, according to Mittal. Instead, they should focus on prevention. Mittal advised maintaining adequate protein intake, avoiding excessive calorie restriction, and ensuring sufficient iron, zinc, and other micronutrients. If someone notices increased shedding, particularly after three to six months, they should seek assessment early rather than assuming it is permanent. A specialist can identify whether this is temporary telogen effluvium or an unrelated hair condition requiring different treatment.
General tips for managing non-scarring alopecia include limiting the use of heated hair tools such as hairdryers, as well as hair bleaching, and stopping smoking. These suggestions were offered in the article.
Individuals taking GLP-1 medications for type 2 diabetes should be aware of all options available to them, which could include SGLT-2 inhibitors and DPP-4 inhibitors, depending on individual circumstances. It is particularly important for people to be aware of the risk of hair loss in cases where they already have an increased risk of alopecia. While the absolute risk is low, awareness can help patients make informed decisions about their treatment plan.
Peptides referenced: Semaglutide, GLP-1.
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