Emerging studies and patient reports suggest GLP-1 medicines may alter taste and smell, but researchers say the effects appear uncommon and remain poorly understood.
People taking GLP-1 medicines for diabetes and weight loss are reporting an unexpected side effect: familiar foods, perfumes and other scents can seem less appealing, or even unpleasant. Researchers say the pattern is beginning to show up in studies as well, although it is still not clear how often it happens or what it means for appetite and eating behaviour. Prof. Gal Dubnov-Raz, who directs the obesity clinic at Safra Children’s Hospital at Sheba Medical Centre in Tel HaShomer, told the Israeli outlet that some patients have described changes in how they perceive fragrances after starting treatment.
The issue has attracted attention beyond medicine. According to the report, major beauty companies including L’Oreal are studying whether GLP-1 drugs are linked to shifting fragrance preferences. Some users appear to lose interest in scents they once liked, while others are drawn to different perfumes. One theory is that, because these drugs can reduce the pleasure people get from food, patients may look for enjoyment elsewhere, including in scent-based products. But that remains speculative, and specialists caution that the biological mechanism has yet to be established.
Evidence is starting to accumulate. A retrospective study published in JAMA Otolaryngology-Head & Neck Surgery found that adults with type 2 diabetes who used GLP-1 medicines had a higher risk of smell and taste disturbances than comparable patients on other diabetes treatments. The study, which analysed records from nearly 877,000 adults, found the absolute number of reported cases was still low. Over two years, the risk was 48% higher overall, with a larger increase for smell problems than for taste.
Separate research has pointed in a similar direction. A study in Physiology & Behavior found that 85% of participants taking GLP-1 receptor agonists performed worse on taste testing than matched controls, with reduced sensitivity across all five basic taste categories: sweet, salty, sour, bitter and umami. In that smaller study, fewer than a quarter of participants noticed any decline themselves, and the researchers did not find evidence of a change in smell. That leaves open a key question: whether these sensory shifts are strong enough to help explain why some people eat less while taking the drugs.
Dubnov-Raz said the leading theory is that GLP-1 medicines may affect sensory pathways in the brain directly, but he stressed that more work is needed. Even data suggesting that users spend more on perfume do not prove a change in fragrance preferences, because those consumers are also spending more on cosmetics more broadly. For now, the safest conclusion is that taste and smell changes may be real, but they appear to be uncommon and poorly understood, and there is not yet enough evidence to justify products designed specifically for GLP-1 users.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
