Highlight
Effects of acute resistant starch consumption on postprandial glucose and insulin responses and oxidative stress parameters in Hispanic women
Figure 1. Blood glucose response of Hispanic women after consumption of resistant starch (RS) and control granola bars
Achievement/Results
NSF-funded researcher Dr. Susan Duncan (Food Science and Technology) in collaboration with Professor Bill Barbeau (Human Nutrition, Foods, and Exercise), and MILES-IGERT trainee Annie Aigster (Human Nutrition, Foods, and Exercise) at Virginia Tech have formulated and characterized cereal based products containing high amounts of resistant starch (RS) and have conducted consumer acceptability testing. The physicochemical and sensory properties of the RS-supplemented cereal based products were evaluated to ensure stability of RS during processing and storage. A critical part of this research was to develop novel cereal based products that are high in RS (a type of starch that physiologically behaves as dietary fiber).
Once the RS-supplemented cereal based products were analyzed, a clinical trial was conducted with Hispanic women (a population at risk for type 2 diabetes) to determine the potential health benefits of RS in blood glucose, insulin, and oxidative stress parameters. Type 2 diabetes (T2D) is a disease that has reached epidemic proportions in developed countries. Type 2 diabetes is characterized by high blood glucose, high blood insulin, and insulin resistance. There are over 23 million people in the U.S. who have diabetes. Type 2 diabetes is twice as common in the Hispanic/Latino population than in non-Hispanic whites. The increased incidence of T2D may be related to an increase in reactive oxygen species (ROS), leading to oxidative stress. Oxidative stress resulting from the production of ROS has been suggested as the cause for development of insulin resistance, beta-cell dysfunction, impaired blood glucose tolerance and T2D. Resistant starch (RS) defined as starch not absorbed in the small intestine of healthy individuals, may promote beneficial physiological effects including laxation, and blood glucose attenuation.
The purpose of this study was to evaluate the acute effects of ingestion of a granola bar containing ~18 grams of RS compared to a control granola bar (~0 grams RS) on postprandial glucose and insulin responses and oxidative stress parameters in Hispanic women. Results from the human feeding study indicated that consumption of RS-supplemented cereals resulted in lowered glucose response after 30 minutes of consumption compared to cereal products with no RS (Figure 1).
Address Goals
Findings from this research may help elucidate the potential role of RS as a functional ingredient and may have a tremendous economic impact as the total medical costs associated with diabetes in the U.S. alone amount to $132 billion dollars a year. These costs could be lowered by dietary modification and further evidence supporting the potential health benefits of RS in populations at risk for type 2 diabetes development. Resistant starch has gained recent attention from food and nutritionists scientists for its role in reducing the risk of type 2 diabetes, colon cancer, laxation, and obesity due to satiety effects among other health-promoting benefits. Many questions on the physicochemical characteristics of RS, functionality in food systems, and biological mechanisms in the human body remain unknown. This study advances the knowledge of RS to help those individuals at risk for type 2 diabetes and potentially decrease the medical costs associated with this disease in the U.S.
