What is the medical condition called where the body does not produce or properly use insulin?

The medical condition where the body does not produce or properly use insulin is known as diabetes, specifically diabetes mellitus. In this condition, individuals can experience elevated blood sugar levels due to inadequate insulin production by the pancreas or the body's inability to effectively use the insulin available. Insulin is a crucial hormone that helps regulate blood glucose levels, facilitating the entry of glucose into cells for energy.

Diabetes mellitus encompasses various types, including Type 1 diabetes, where the body produces little to no insulin, and Type 2 diabetes, where the body's cells become resistant to insulin's effects. This results in chronic hyperglycemia, or high blood sugar levels, which can lead to numerous complications if not managed effectively.

Hyperglycemia refers to the symptom of elevated blood glucose levels rather than the underlying cause related to insulin. Thyroid dysfunction involves issues with thyroid hormone production and is unrelated to insulin or glucose metabolism. Insulinoma is a rare tumor of the pancreas that can cause excessive insulin production, leading to hypoglycemia, not a deficiency. Thus, diabetes mellitus accurately describes the condition characterized by insulin production or usage issues.