GLP-1 trials reveal diet quality gap as companion products boom

Many GLP-1 clinical trials are not tracking what patients are consuming, pointing to a gap in the weight-loss market. Nutrition Insight asks FrieslandCampina Ingredients, Probi, Roquette, and HTBA what this data gap means for nutrition industry innovators developing solutions for GLP-1 users today. 

A scoping review in Advances in Nutrition from last year of 129 randomized trials investigated liraglutide, semaglutide, or tirzepatide in humans. Only 57 trials included lifestyle modification activities, and only 36 recorded diet quality and food intake. Of this, only 10 trials reported outcomes, while only 17 trials assessed food cravings or eating behavior.

Despite the mainstream appeal of GLP-1 agonist drugs, researchers flag that most trials lacked detailed reporting on nutritional behaviors.

From gap to opportunity

There are real implications for how companion products are being developed since the industry is working with an insufficient picture of consumers’ eating behaviors, notes Penny Antonopoulos, marketing manager for Performance and Active Nutrition at FrieslandCampina Ingredients.

“The clinical evidence base for GLP-1 medications is strong on weight loss outcomes, but notably light on dietary data in key areas such as what users are actually eating and how their nutritional status shifts over time.” 

“This highlights an opportunity for the industry: designing solutions around how people actually eat when using GLP‑1 medications. Products that are too large, too heavy, or require too much effort simply don’t endure in this context. Success will depend on creating nutrient-dense solutions that are easy to consume, support digestive comfort, and fit naturally into low-appetite moments.”

“Feeding the microbiome”

Based on the lack of detailed dietary tracking in GLP‑1 trials, Brandy Webb, ND, scientific affairs manager at Probi USA, infers that it leaves the nutrition industry navigating an “incomplete map.”

“We don’t yet have strong evidence on how specific nutrients or food patterns interact with these drugs, so, while many current products are built on well-reasoned hypotheses, they are not substantiated by trial-driven dietary data.”

“From a microbiome lens, this gap matters. GLP‑1s reduce appetite and slow gastric emptying, which often leads to lower fiber and micronutrient intake — key inputs for a healthy gut. Over time, that can lead to nutrient deficiencies as well as shrink microbial diversity and reduce production of beneficial short-chain fatty acids (SCFAs).”

Furthermore, she explains that such consequences can be opportunities for precision nutrition solutions and targeted biotic solutions to “feed the microbiome” even when overall consumption drops.

Only 17 of 129 GLP-1 trials assessed food cravings or eating behavior in participants.“In the first case, products must supply nutrients relevant to GLP-1 users, such as fiber, protein, and certain micronutrients, using formats that are easy to digest. In the latter case, the most promising approaches will focus on bacterial strains, including specific probiotic strains, and substrates that support SCFA production, gut barrier function, and gut-brain signaling.”

Respond to what is known

Elodie Dehay Harmel, Nutrition & Health research scientist at Roquette, reflects on clinical trials with GLP-1 receptor agonists, pointing out that they have mainly focused on showing effects on certain physiological outcomes such as glycemic control, appetite regulation, and weight loss.

“While overall caloric intake is typically assessed, detailed tracking of dietary composition is rarely included, leaving a gap in our understanding of what consumers actually eat. However, while scientists may not always track what GLP-1 analog users are eating, those taking the medications often do, providing useful real-world insights.” 

“Even for those who don’t, there are certainly actions that the industry can, and should, take to support this growing consumer group,” she stresses. “We know that GLP-1 medications can reduce appetite, so developing smaller, nutrient-dense portions is a smart response to changing eating habits.”

Concurrently, GLP-1 analog users are also encouraged to have more active lifestyles during treatment, which means convenience on-the-go becomes important to consider, Dehay Harmel notes.

“Consumers also want to quickly understand how a product supports their goals. Brands should clearly communicate the nutritional role of a food or supplement, whether that’s providing protein to support satiety and muscle health, fiber to support digestive wellness, or other key nutrients — such as energy.”

GLP-1 users are increasingly encouraged to maintain active lifestyles during treatment, making on-the-go nutrition convenience a key product consideration.“Ultimately, solutions for GLP-1 analog users need to be simple to understand and enjoyable to consume, while giving consumers the confidence that they align with their weight-management goals,” she explains. “Although the industry is already starting to respond to these needs, we would welcome more studies that track what users are actually eating to help inform future innovation.”

Maintaining muscle mass

Noting a consequential gap to come out of the GLP-1 trial data, Teresa Pellicer, product manager of Biotechnology at HTBA, flags that up to 40–60% of GLP-1-supported weight loss can come from lean muscle mass loss, not fat, if it is not well managed.

“But muscle loss was rarely a primary endpoint in the original studies, and the industry is now catching up with a physiological reality that wasn’t fully measured when these drugs were approved.”

“What this points to is a need to shift the conversation from weight loss as a single outcome to the quality of that weight loss. Losing weight matters; losing it while preserving muscle, maintaining energy, and supporting metabolic health is a fundamentally different challenge.”

Addressing this challenge, Pellicer highlights HTBA’s Leanara — a dual-effect companion ingredient — which combines bioflavonoids with highly bioavailable vitamin B12 to fill the nutritional gaps GLP-1 users face “beyond the number on the scale.”