Sultan Kosen, Tallest Man In The World, 2 Meters 47 Centimeters, Turkey

Adult height between populations often differs significantly. For example, the average height of women from the Czech Republic is greater than that of men from Malawi. This may be caused by genetic differences, childhood lifestyle differences (nutrition, sleep patterns, physical labor), or both.
At 2.57 m (8 ft 5 in), Leonid Stadnyk, of Zhytomyr Oblast, Ukraine, is believed to be the world's tallest living man, although his height is disputed because of his refusal to be measured. The current proven tallest man is Sultan Kösen, of Turkey, who stands at 2.47 m (8 ft 1 in), overtaking previous world-record holder Bao Xishun, of Inner Mongolia, China, who is 2.36 m (7 ft 9 in) (He Pingping, the former shortest man in the world, was also from Inner Mongolia). The tallest man in modern history was Robert Pershing Wadlow (1918–1940), from Illinois, in the United States, who was 2.72 m (8 ft 11 in) at the time of his death. Until her death in 2008, Sandy Allen was the tallest woman in the world, at 2.32 m (7 ft 7 1⁄2 in). Yao Defen of China is claimed to be the tallest living woman in the world at 2.33 m (7 ft 7 1⁄2 in), but this is not confirmed by the Guinness Book of World Records.
The maximal height that a person attains in adulthood is not maintained throughout a long life. Depending on sex, genetic and environmental factors, shrinkage of stature may begin in middle age in some individuals but is universal in the extremely aged. This decrease in height is due to such factors as decreased height of inter-vertebral discs because of desiccation, atrophy of soft tissues and postural changes secondary to degenerative disease.