Wadlow reached 8 ft 11.1 in (2.72 m) in height and weighed 439 lb (199 kg) at his death at age 22. His great size and his continued growth in adulthood were due to hyperplasia of his pituitary gland, which results in an abnormally high level of human growth hormone (HGH). Even by the time of his death, there was no indication that his growth had ended.
