A food with a high glycemic index such as sugar will send a person's blood glucose level up quickly. The body will then respond by producing high levels of insulin. Insulin is a hormone that promotes the conversion of blood glucose into fat. Diabetics must avoid high glycemic foods since they are unable to produce the necessary insulin to counteract the blood glucose. High blood glucose levels are extremely unhealthy.
Most people regard sugar as unhealthy.
This is hard to believe, but it is true. High glycemic foods cause blood glucose levels to rise, which causes the body to produce insulin. Insulin causes blood sugar to be stored away. This causes blood glucose levels to drop. Low blood glucose levels trigger the body to decide it needs more energy.