One widely available product that contains uncooked cornstarch as a key ingredient is ExtendBar, a brand of nutrition bar that was developed by pediatric endocrinologist Francine Kaufman, who was searching for a way to help her patients stabilize their blood glucose level over extended periods. In her research, she found that mixing a relatively small amount of uncooked cornstarch with particular amounts of fat, protein, and other carbohydrates resulted in a substance that was slowly absorbed over nine hours. Her formulation is now the basis of ExtendBar snack bars, as well as ExtendCrisps, which are crispy, baked, savory snacks, ExtendDrizzles, which are sweet snacks, and ExtendShakes, powdered beverage mixes.
Since they can help prevent hypoglycemia, products containing uncooked cornstarch may be useful in a number of situations. Eaten before bedtime, they can lower the risk of hypoglycemia during the night. As a between-meal snack, they may help to control both blood glucose level and appetite since they are digested so slowly. And eaten before exercise, a snack containing uncooked cornstarch can aid in preventing late-onset post-exercise hypoglycemia. This occurs when muscles continue to replenish their glucose stores hours after physical activity, leading to a sometimes-surprising drop in blood glucose level as much as 8–12 hours after exercise.
Choosing a cornstarch product
If you decide to try a cornstarch-based bar, crisp, or shake, pay close attention to the variety you choose and the details on the Nutrition Facts food label. These products do contain calories, and some of the carbohydrate may need to be counted in your meal plan.
ExtendBars come in two varieties, both of which contain about 150 calories per serving and are sweetened with sugar alcohols. (Sugar alcohols are a type of carbohydrate that in most cases is incompletely digested and absorbed in the intestine, so they provide fewer than 4 calories per gram. An exception to this is glycerine, which is classified as a sugar alcohol but is completely metabolized and provides 4 calories per gram.) The “Crunch” variety contains 29–30 grams of carbohydrate and 10 grams of sugar, while the “Delight” formula is sugar free, containing 20–21 grams of carbohydrate and 0–1 gram of sugar.
The maker of ExtendBars suggests that if you are counting your carbohydrates — whether it’s to help you manage your meal plan or to determine if an adjustment to your insulin is appropriate — you should count only the carbohydrates that have a short-term effect on blood glucose level. These carbohydrates are referred to as “faster-acting” or “net” carbs. The remaining, “slower-acting” carbohydrates are broken down and converted to glucose so slowly that they have minimal effect on blood glucose level.
In the ExtendBar Delight formula, the carbohydrate from the fiber, glycerine, maltitol, and uncooked cornstarch converts slowly and has a minimal effect on blood glucose level. Therefore, only 1–2 grams out of the total grams of carbohydrate in the Delight formula have a short-term effect on blood glucose. In the Crunch variety, the carbohydrate from uncooked cornstarch, maltitol, and fructose is slower-acting; as a result, only 10–11 grams of the total carbohydrate have a short-term effect on blood glucose level.
Individual packets of ExtendCrisps provide 120–130 calories and 16–17 grams of carbohydrate. The manufacturer suggests that only 8–9 of the total grams of carbohydrate have a short-term impact on blood glucose. Individual bags of ExtendDrizzles provide 130 calories and 17 grams of carbohydrate.
ExtendShakes, when prepared with water, provide 110 calories and 12 grams of carbohydrate. The manufacturer suggests that only 2 of the total grams of carbohydrate have a short-term impact on blood glucose. (If the mix is prepared with milk, the calories and grams of carbohydrate in the milk must be counted as well.)