Diabetes isn't curable because of the cells that produce insulin, the hormone key to helping the body break down blood sugar. These are the beta cells in the pancreas that either can't make enough insulin (type 2 diabetes) or are attacked by the immune system (type 1 diabetes). Without fixing the pancreas's ability to produce insulin that meets the body's needs, you can't cure diabetes.
The only treatment options aim to improve the condition and ensure that blood sugar levels stay within normal parameters for as long as possible.