An Endocrinologist is an Internal Medicine, or for children - a Pediatric, medical doctor with additional qualifications enabling specialization in the evaluation and management of disorders of the endocrine glands, which regulate the body’s hormones which in turn regulate many aspects of metabolism. This specialist manages conditions such as type 1 diabetes, hyper and underactive thyroid disorders, metabolic and nutritional disorders, refractory obesity, pituitary diseases, and sexual disorders and dysfunctions due to hormone disturbances.  In children, diseases can also include growth failure or excess, early or late pubertal development and other atypical gender development issues, and birth defects.