The tallest man in medical history for whom there is irrefutable evidence is Robert Pershing Wadlow
He was born at exactly 6:30 a.m. at Alton, Illinois, in the United States of America on 22 February 1918. As at the last time he was measured on 27 June 1940, his height was found to be 2.72 M (8 ft 11.1 in) tall.
Source: Guiness world records

Wadlow died at 1:30 a.m. on 15 July 1940 (at the age of 22) in a hotel in Manistee, Michigan, as a result of a septic blister on his right ankle caused by a brace, which had been poorly fitted only a week earlier.

He was buried in Oakwood Cemetery, Alton in a coffin measuring 3.28 m (10 ft 9 in) long, 81 cm (32 in) wide and 76 cm (30 in) deep.

His greatest recorded weight was 222.71 kg (35 st 1l b) on his 21st birthday and he weighed 199 kg (31 st 5 lb) at the time of his death.

His shoe size was 37AA (47 cm (18.5 in) long) and his hands measured 32.4 cm (12.75 in) from the wrist to the tip of the middle finger.

He wore a size 25 ring.
His arm span was 2.88 m (9ft 5.75 in) and his peak daily food consumption was 8000 calories.

At the age of nine, he was able to carry his father Harold F. Wadlow (September 1967) later Mayor of Alton, who stood 1.8 m (5 ft 11 in) and weighed 77 kg (170 lb), up the stairs of the family home.
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