Insulin (in-suh-lin): A hormone made by the cells in your pancreas. Insulin helps your body store the glucose (sugar) from your meals. If you have diabetes and your pancreas is unable to make enough of this hormone, you may be prescribed medicines to help your liver make more or make your muscles more sensitive to the available insulin. If these medicines are not enough, you may be prescribed insulin shots.
In a way, moderate-intensity physical activity is that "magic pill" a lot of people are looking for, because the health benefits go beyond keeping your waistline trim: Not only can it reduce your risk of cancer, stroke, diabetes and heart attacks, but studies have shown that physical activity can significantly improve the moods of patients with major depressive disorders.