The statement that is true regarding diabetes is:
Diabetes is an autoimmune disease.
However, it's important to clarify that this statement primarily applies to Type 1 diabetes, which is considered an autoimmune condition where the body's immune system attacks insulin-producing cells in the pancreas. Type 2 diabetes, on the other hand, is primarily related to insulin resistance and metabolic factors. The other statements provided are not accurate. Diabetes does not always start at an early age, it is not a type of cancer, and it is not caused by abnormal blood cells.