Robert Wadlow, the World’s Tallest Man

From Wikipedia:
Robert Pershing Wadlow (February 22, 1918 – July 15, 1940) is the tallest person in medical history for whom there is irrefutable evidence. He is often known as the "Alton Giant" because of his Alton, Illinois hometown.

Wadlow reached an unprecedented 8 feet 11.09 inches (2.72 m) in height and weighed 440 pounds (199 kg) at his death. His great size and his continued growth in adulthood was due to hypertrophy of his pituitary gland which results in an abnormally high level of human growth hormone. He showed no indication of an end to his growth even at the time of his death.
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