Tucson Standard

Ozempic, known generically as semaglutide, has become prominent in the weight-loss market for its rapid results. While many use the drug primarily to reduce body weight, it is mainly prescribed for treating type 2 diabetes in adults and can be expensive without insurance coverage. However, new research suggests that weight loss and improved glucose control might be achievable through dietary changes rather than medication.

Frank Duca, an associate professor at the University of Arizona's Department of Animal and Comparative Biomedical Sciences within the College of Agriculture, Life and Environmental Sciences, led a study indicating that consuming foods rich in beta-glucan—a type of fiber found in oats and barley—can help reduce body weight and obesity. The study was published in The Journal of Nutrition and examined how different fibers affect gut microbiota—the community of microbes responsible for breaking down food in the digestive system.

"We know that fiber is important and beneficial; the problem is that there are so many different types of fiber," Duca said. "We wanted to know what kind of fiber would be most beneficial for weight loss and improvements in glucose homeostasis so that we can inform the community, the consumer, and then also inform the agricultural industry."

The researchers analyzed five different plant-based fibers: pectin, beta-glucan, wheat dextrin, starch, and cellulose. They found that only beta-glucan resulted in reduced body weight and fat as well as improved glucose homeostasis. Beta-glucan is present in various foods such as oats, barley, mushrooms, and yeasts. Future studies will explore how different sources of beta-glucan may vary in effectiveness.

The study highlighted changes in metabolites—molecules produced when gut bacteria interact with fiber—as key to the weight-loss effects observed. Specifically noted was butyrate, a metabolite crucial for colon cell fuel which promotes a healthy gut barrier to reduce systemic inflammation. Butyrate also induces the release of gut peptides like glucagon-like peptide-1 (GLP-1), which regulate gut functions.

Drugs like semaglutide are synthetic versions of GLP-1 designed to stimulate insulin production while helping individuals feel full longer by targeting brain receptors more effectively than naturally occurring GLP-1.

"Part of the benefits of consuming dietary fiber is through the release of GLP-1 and other gut peptides that regulate appetite and body weight," Duca explained. "However, we don't think that's all of the effect. We think that there are other beneficial things that butyrate could be doing that are not gut peptide related, such as improving gut barrier health and targeting peripheral organs like the liver."

Duca's ongoing research aims to identify other types of beneficial fibers for weight reduction. Previous studies from his lab found barley flour effective for promoting weight loss compared to other commercially available flours. Studies involving oligofructose have also shown positive effects. In future work, Duca hopes to collaborate with other researchers to develop enhanced fibers optimizing butyrate release.