As interest in managing metabolic health through diet grows, new approaches like the keto diet and medications such as Ozempic are gaining popularity. The keto diet, which focuses on low carbohydrates and high fat to promote fat burning, has shown promise for weight control and blood sugar management, although it may not be suitable for everyone. Meanwhile, Ozempic, a medication designed for type 2 diabetes, helps lower blood sugar and supports weight loss by regulating insulin and reducing appetite. However, for those seeking natural dietary options, recent research is exploring how plant-based fibers could offer additional pathways to metabolic health without medication.
Diet’s impact on health, especially through the gut’s complex microbial ecosystem, is a hot topic in recent research. Recently, scientists explored how plant-based fibers affect metabolic health in a study published in The Journal of Nutrition. Led by Dr. Frank Duca from the University of Arizona, researchers aimed to find out which types of plant fibers best support metabolic stability by altering gut bacteria and producing beneficial compounds. Dr. Duca and his team, including Elizabeth Howard, Rachel Meyer, Savanna Weninger, and Taylor Martinez from the University of Vienna and Steele Children’s Research Center, tested different types of plant fibers on mice fed a high-fat diet.
Results showed that among the fibers tested—pectin, β-glucan, wheat dextrin, resistant starch, and cellulose—β-glucan stood out for its effectiveness in reducing weight gain and balancing blood sugar. “Dietary fiber is known to help metabolic health, but the specific effects of different fibers remain largely unknown,” Dr. Duca remarked. By investigating five fibers in mice over an 18-week period, researchers found that β-glucan was the only fiber to significantly reduce weight gain, improve glucose regulation, and encourage physical activity levels, indicating higher energy use. In contrast, other fibers, while beneficial in specific ways, did not have the same broad metabolic effects.
Remarkably, the study revealed that only β-glucan led to major reductions in both weight gain and fat levels. Mice on this fiber also showed improved blood sugar control, a key factor in managing conditions like diabetes. The team observed that the mice given β-glucan were more active, which linked with their increased energy use. Higher activity and energy use are often connected to better weight management. Other fibers such as pectin and resistant starch supported gut health but did not produce the same impact on weight control and blood sugar as β-glucan.
Beyond metabolic benefits, each fiber also had unique effects on gut bacteria and the compounds they produce. β-glucan, in particular, boosted levels of a compound called butyrate, known for its positive effects on metabolism. Dr. Duca noted, “Butyrate has been tied to greater energy usage and fat burning, which may be helpful for weight control.” The study suggests that β-glucan may support weight management partly by increasing butyrate, making it a promising dietary choice for those seeking metabolic stability.
Researchers also found that the diversity of gut bacteria plays an essential role in overall metabolic health. Each fiber type changed the mix of bacteria in the gut differently, influencing metabolism in various ways. For example, β-glucan encouraged the growth of bacteria such as Ileibacterium, which has been connected to higher energy use. Meanwhile, wheat dextrin and resistant starch promoted the growth of beneficial bacteria like Akkermansia and Bifidobacterium. However, the study indicated that these bacterial changes alone might not be enough to impact metabolism, as seen in the limited effect of wheat dextrin and resistant starch on weight and blood sugar.
These results point to β-glucan as a potentially effective dietary supplement for people looking to improve their metabolic health. As obesity rates climb worldwide, dietary fibers such as β-glucan may offer a non-medical approach to better metabolic health. The research highlights that not all fibers are the same; each type can affect gut bacteria and health differently.
Overall, while various fibers support gut health, β-glucan appears to be the most effective in managing weight and blood sugar. These findings suggest that β-glucan could be particularly useful for those aiming to improve their metabolic health, perhaps encouraging health professionals to recommend it as part of a balanced diet. Future studies may explore how these findings apply to humans, potentially guiding new dietary recommendations to address obesity and metabolic concerns.
Journal Reference
Duca F.A., Howard E.J., Meyer R.K., Weninger S.N., et al. “Impact of Plant-Based Dietary Fibers on Metabolic Homeostasis in High-Fat Diet Mice via Alterations in the Gut Microbiota and Metabolites.” The Journal of Nutrition, 2024. DOI: https://doi.org/10.1016/j.tjnut.2024.05.003
About the Author
Dr. Duca received his undergraduate degree in Biomedical Engineering and his M.S. degree in Nutritional Sciences from The Pennsylvania State University. Dr. Duca received his PhD from Université Pierre-et-Marie-Curie (now Sorbonne Université), working on the role of postingestive gastrointestinal peptides in the control of food intake, and the impact of gut-brain signaling in the development of obesity during high-fat feeding. He was a Banting postdoctoral fellow, under the mentorship of Dr. Tony Lam at Toronto General Hospital Research Institute, examining the role of small intestinal nutrient sensing on regulating glucose homeostasis and the impact of the gut microbiota. Dr. Duca’s laboratory at the University of Arizona is interested in the role of the gut-brain axis in the development of obesity and diabetes. His lab focuses on how different environmental factors, like diet, temperature, and toxic exposures, can impact energy and glucose homeostasis. Additionally, his lab studies how alterations in the gut microbiota can be both a factor and treatment for metabolic diseases via direct host-microbe interactions, as well as through the production of bacterially-derived metabolites that can have an impact both locally in the intestine, as well as peripherally, like at the liver, pancreas, adipose, and brain.
