FOOD AMYLOSE CONTENT ON POSTPRANDIAL GLUCOSE AND INSULIN RESPONSES

Authors: BEHALL, KAY; SCHOLFIELD, DANIEL - NTL AGRICULTURAL LIBRARY

Submitted to: American Association of Cereal Chemists
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2005
Publication Date: 9/1/2005
Citation: Behall, K.M., Scholfield, D.J. 2005. Food amylose content on postprandial glucose and insulin responses. American Association of Cereal Chemists. 82:654-659.

Interpretive Summary: Most health organizations recommend an increase in consumption of dietary fiber since high fiber diets have been reported to have beneficial health effects in individuals with diseases such as cardiovascular disease, hypertension, colon cancer, and diabetes. However, the median dietary fiber intakes in the United States were 17.0 and 13.8 g/d for men and women, respectively. Maturity onset diabetes, characterized by elevated blood glucose levels and insulin resistance, has increased in prevalence in the US as the average age of our population increases. It has been shown that consumption of a high amylose starch meal results in a beneficial reduction in insulin and glucose levels. This study was conducted to determine whether a beneficial interaction occurred between native corn fiber in cornmeal and high-amylose cornstarch on health parameters. Half of the subjects had elevated insulin responses to a glucose tolerance. No gender difference was observed between the 12 men and 12 women. The 12 hyperinsulinemic (higher insulin response to a glucose challenge than typical) subjects had significantly higher insulin and glucose responses and areas under the curve than did the control subjects. Average glucose, insulin, and glucagon values were usually lower after the consumption of test meals containing corn fiber. Insulin and glucose responses, but not glucagon response, were significantly greater after products made with amylopectin than with amylose. Average plasma glucose and insulin areas under the curve after amylose test meals were approximately half of those after amylopectin test meals. The glucose and insulin responses agree with earlier work with amylose. The presence of fiber from cornmeal had less effect on the response curves of glucose, insulin, and glucagon than did the type of starch consumed. Health providers should be aware of the health benefits of this slowly digested starch. Although the corn fiber did not greatly reduce glucose or insulin other health benefits occur with increased fiber intake. Nutritionists, scientists and health care professionals will benefit by having additional knowledge of this low glycemic index (slowly digested starch) food source.

Technical Abstract: Beneficial reduction in glycemic response has been observed after consumption of some high amylose products. This study examined the effect of varying the moisture content and the particle size of the starch in the food product. Twelve men and 12 women consumed corn chips or corn muffins made with starch or starch plus cornmeal from standard corn (30% amylose, 70% amylopectin) or high (70%) amylose corn. Half of the subjects were hyperinsulinemic based on a prestudy glucose challenge. No gender differences were observed. The hyperinsulinemic subjects had significantly higher insulin and glucose responses and area under the curve as compared to the normal responders. Average glucose, insulin and glucagon were usually lower after muffins compared to chips or products containing cornmeal. Insulin and glucose responses, but not glucagon, were significantly lower after the consumption of products made with high-amylose compared to standard cornstarch and in control vs hyperinsulinemic subjects. Average plasma glucose and insulin area under the curves after high-amylose products were approximately half those after standard cornstarch. The presence of corn meal (increasing the particle size of the starch) had less effect on the response of glucose, insulin or glucagon than the type of starch or food consumed.