Red Raspberries Show Promise for Insulin-Resistant Adults

Move over, apples. Red raspberries are getting their day in the sun with the assistance of research coming out of Illinois Tech’s School of Applied Technology. Department of Food Science and Nutrition doctoral candidate Xuhuiqun Zhang presented the results of her project “Effect of Red Raspberry (Rubus idaeus L.) Consumption with or without fructo-oligosaccharide on Metabolic Indices: a Single-Blinded Randomized, Crossover Clinical Trial” at the 2019 American Society for Nutrition annual conference from June 8–11 in Baltimore, and was selected to additionally participate in the conference’s Clinical Emerging Leaders Award Competition and the Emerging Leaders in Nutrition Science Poster Competition. Zhang’s entry placed third in the poster event.

“Red raspberries contain a unique polyphenol profile associated with cardio-metabolic benefits,” says Zhang. “Fructo-oligosaccharides [plant sugars], as prebiotics [compounds that encourage the growth of beneficial microorganisms], present an approach to augment the cardio-metabolic benefits of red raspberries through their known effects in modifying the gut microbiota composition.”

The study examined the glucose and insulin responses and the plasma lipid profiles of insulin-resistant and metabolically healthy reference adults in a 12-week single-blinded, randomized, crossover clinical trial. Participants consumed either one cup of red raspberries or red raspberries supplemented with fructo-oligosaccharides per day. Zhang determined that after four weeks, the plain red raspberries improved the glycemic and lipid profiles of insulin-resistant individuals. The addition of fructo-oligosaccharides enhanced the glycemic benefits but reduced the lipid-lowering effect of the red raspberries.