Common snacks consumed by adults or children consist of sugar-based candies and beverages with little nutrient value beyond energy. Sun-dried raisins are a convenient, easy-to-pack snack that provides vitamins and minerals, such as potassium and iron, phytochemicals (antioxidants), tartaric acid, and dietary fiber, both insoluble and soluble. Simple sugars, such as those found in snack candies and beverages, are known to cause a “let down” effect when taken on an empty stomach. They cause an immediate surge in blood glucose (blood sugar), followed by a gradual decrease that reaches levels lower than those present at fasting after three hours (rebound hypoglycemia). On the other hand, foods high in fiber elicit a more moderate rise in blood sugar and, even more important, do not have this “let down” effect.

Ten healthy men and women, 22-46 years old, were asked to consume one of three snacks, with equal energy content (360g kcal): sugar, glucose, or sun-dried raisins. Their blood sugar and insulin were measured before and after eating the snack, over the course of 3 hours. The participants repeated the test twice, one week apart, to ensure that all of them consumed each of the three snacks.

Both raisins and table sugar caused a more moderate rise in blood sugar after 30 minutes, compared to glucose, but only the raisins sustained the blood sugar levels to close to fasting after three hours, whereas glucose and table sugar caused a drop to levels significantly different from time zero.

These results strongly suggest that, sun-dried raisins, compared to fiber-free, sugar-based candies and beverages, are a more nutritious, convenient snack food choice that does not cause the “let down” response commonly seen with these popular snacks.

Spiller GA, Moynihan S and Butterfield G. Effects of sun-dried raisins on serum glucose: support for a convenient, plant-based snack food. Veg Nutrition: An International Journal 2(3): 93-95, 1998.