A preferred starch for diabetics?

A preferred starch for diabetics?

Scientists had long thought that the body digested all starches identically and at a similar pace. Moreover, they had assumed that because starches are chains of many sugars, they would take longer to break down into glucose (blood sugar) than would simple sugars like sucrose (table sugar). But intrigued by a published report indicating that some starches break down and enter the blood as quickly as do simple sugars, research nutritionist Kay Behall and her colleagues decided to see if they could identify which were the quick-digesting food starches. Their finding may one day benefit diabetics attempting to control blood sugar levels through diet.

Food starches come in two forms: amalose and amalopectin. Most foods contain both. Behall, at the Agriculture Department's Human Nutrition Research Center in Beltsville, Md., fed breakfasts of predominantly amalose-based crackers, predominantly amalopectin-based crackers or sucrose patties to 25 healthy, nondiabetic adults who had fasted since the night before. During succeeding weeks she offered each subject another of these breakfasts until all had eaten each food once. Blood levels of glucose and insulin were recorded before each meal and at intervals afterward.

Though all diners started their meals with comparable blood levels of insulin and glucose, within 30 minutes of eating, the amalopectin and sucrose eaters had elevated levels of both relative to the amalose eaters: Their blood sugar was an average of 15 percent higher than the amalose diners', and their insulin levels an average of 40 percent higher. Over the next 2.5 hours, blood levels of both glucose and insulin in all three groups gradually returned to about the fasting level.

Amalose, concludes Behall, not only lowered peak blood sugar levels but also slowed sugar delivery into the blood--a potential benefit to diabetics. Moreover, she notes, amalose allowed the body to rid the blood of sugar using less insulin.