Endocrine diseases are disorders of the endocrine system, which is made up of glands that produce and secrete hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood, among other things. Endocrine diseases can be caused by a variety of factors, including genetic defects, autoimmune diseases, infections, tumors, and other environmental factors. Common endocrine diseases include diabetes, thyroid disorders, and adrenal disorders.