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 pancreas also makes another type of hormone called glucagon. Glucagon is produced in the alpha cells of the pancreas islets and is released when the blood glucose level is too low. Glucagon works almost exactly in reverse to insulin, and promotes an increase in blood glucose levels.