What are Type 1 and Type 2 Diabetes? Type 1 and type 2 diabetes are different forms of diabetes mellitus, which is a chronic condition that leads to elevated blood sugar levels. Type 1 diabetes is an autoimmune disease. In this condition, the body’s immune system targets the insulin-producing cells, causing a deficiency in insulin production. In type 2 diabetes, the body either doesn’t make enough insulin or cannot effectively utilize it. This state is called insulin resistance and can cause ele