Hyperinsulism or hyperinsulinemia is a condition in which the body's cells do not respond properly to insulin, the hormone that functions to control blood sugar levels. Insulin transports nutrients (mainly glucose) across cell membranes.

Insulin resistance

With insulin resistance, less glucose is absorbed from the blood, resulting in higher insulin secretion.

Insulinoma

Hypoglycemia due to hyperinsulinism can be a feature of insulinoma, a (usually benign) tumor that secretes insulin.