Robert Wadlow was the tallest person in history (1918-1940). He was 8 ft 11.1 in tall or 2.72 meters. His great size is due to his pituitary gland having a proliferation of cells. This resulted in increased levels of human growth hormone.
His size took a toll on him as he required leg braces to walk. 11 days before his death, a faulty brace irritated his ankle and caused a blister and soon a parasitic infection. Doctors tried to treat him with surgery & blood transfusion but his condition worsened. He had auto-immune disorder as well, which meant his immune system attacked healthy cells & tissues. He died in his sleep at age 22.
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