GLP-1 weight loss therapies may weaken taste, experts flag

New research uncovers significant sensory impacts of glucagon-like peptide-1 receptor agonists (GLP-1 RAs), medications commonly prescribed for weight loss and obesity management.

Researchers at the University of Pennsylvania found that GLP-1 RAs significantly impair taste function across all five basic taste qualities: sweet, sour, salty, bitter, and umami. Their findings shed light on a previously underexplored consequence of these drugs.

The findings are relevant to users of appetite-suppressing pharmaceuticals for rapid weight loss, who face temporary and long-term side effects related to consuming less nutritious foods, including critical nutritional gaps and muscle loss.

The study, published in Physiology & Behavior, was led by Dr. Rafa Khan and Dr. Richard Doty. It employed olfactory assessment tools, including the 53-item Waterless Empirical Taste Test (WETT) and the 40-item University of Pennsylvania Smell Identification Test (UPSIT).

The researchers compared a sample of 46 individuals taking GLP-1 RAs to 46 matched controls. Results revealed that 85% of GLP-1 RA users had significantly diminished taste perception, with an average WETT score 29% lower than that of the control group.

This research demonstrates, for the first time, that GLP-1 receptor agonists negatively impact a major sensory system. The reduction in taste perception could have profound implications for dietary choices, nutrition, and overall metabolic health.

Additionally, the study notes that participants experiencing common GLP-1 RA-related side effects, such as nausea and diarrhea, showed better taste and smell function than those without these symptoms. However, overall smell function was not significantly impacted.

GLP-1 popularity drives up nutritional solutions

GLP-1 RAs, initially developed for diabetes management, have become increasingly popular for weight loss, with over 10% of the US population taking these medications.

Blanket policy reform is one factor driving up market activity around medical weight loss. The US government has floated lowering costs and expanding the accessibility of weight-loss medications like GLP-1 drugs to obese patients without other medical conditions.

The growing demand for GLP-1 weight management has increased activity in complementary nutritional solutions. Kelker Pharma recently introduced Nutrilinq Genesis, touted as the “first science-backed” nutritional support system for GLP-1 therapy patients.

In the mobile app space, weight management app Noom has revealed a major update to its GLP-1 Companion service to accompany and optimize popular GLP-1 drug therapies.

ADM recently identified five unique needs for GLP-1 consumers, which it addresses with its ingredient solutions. “Three of them are when the consumer is actively on a GLP-1 drug, and two of them happen when the consumer comes off the drug,” Brad Schwan, VP of marketing at the company, told Nutrition Insight at SupplySide West 2024.