Fruits and vegetables contain soluble and insoluble fiber in varying proportions. When you eat soluble fiber, it absorbs water to form a gel-like mass, which helps you feel full and provides other health benefits. It prevents a surge in blood sugar after you eat by slowing down the absorption of carbohydrates.
If the blood glucose level falls to dangerous levels (as in very heavy exercise or lack of food for extended periods), the Alpha cells of the pancreas release glucagon, a hormone whose effects on liver cells act to increase blood glucose levels.
The overall effect of these hormones is to reduce the production of sugar by the liver during a meal to prevent it from getting too high. The good news is that amylin is now available as a medicine to control post-meal glucagon and blood sugar in individuals with type 1 diabetes.