Which organ in the human body produces insulin?

The pancreas is the organ responsible for producing insulin in the human body. Insulin is a crucial hormone that helps regulate blood sugar levels by facilitating the uptake of glucose into the cells for energy or storage as fat. The pancreas contains clusters of cells known as the islets of Langerhans, which specifically include beta cells that produce and secrete insulin in response to rising blood glucose levels after eating.

The liver, while critical in metabolism and glucose storage, does not produce insulin; it instead responds to insulin by helping to manage blood sugar levels. The kidneys play roles in filtering blood and regulating various substances, but they do not produce insulin either. The stomach's primary function is related to digestion, breaking down food to prepare it for nutrient absorption rather than hormone production like insulin. Therefore, the pancreas stands out as the only organ in this context that produces insulin.