Which health alteration is characterized by the lack of insulin production?

Diabetes mellitus type 1 is characterized by an autoimmune destruction of the insulin-producing beta cells in the pancreas, leading to little or no insulin production. This condition typically arises early in life and results in the patient's inability to regulate blood glucose levels effectively, necessitating lifelong management through insulin therapy. In contrast, diabetes mellitus type 2 involves insulin resistance and a gradual decrease in insulin production, but it is not primarily caused by a lack of insulin production from the outset. Gestational diabetes occurs during pregnancy and does not involve a complete lack of insulin production but rather an insulin resistance that arises due to hormonal changes. Hypoglycemia refers to low blood sugar levels and is not a type of diabetes but a condition that can occur in individuals with diabetes or those without diabetes under certain circumstances. Therefore, the defining characteristic of diabetes mellitus type 1 is the absence of insulin production.