Endocrinology concerns the study of glands, which are organs that produce hormones and other substances that help regulate bodily functions. Endocrinology is a branch of medicine that focuses on the diagnosis and treatment of diseases related to the endocrine system, which is made up of glands that secrete hormones into the bloodstream. Endocrinologists specialize in understanding how hormones affect the body and how to treat conditions caused by hormone imbalances.