What is type 1 diabetes?

Diabetes is a disease in which blood glucose levels are too high. In type 1 diabetes (T1D), the immune system attacks and destroys pancreatic beta cells that make insulin — a hormone that tells cells to absorb and use glucose for energy.^[1] T1D usually begins during childhood or adolescence, but it can occur at any age. The prevalence of T1D tends to increase as you travel away from the equator, with rates substantially greater in Finland and other Northern European nations than in China and Venezuela.^[2]