I recall my Dad saying something about height being variable, which seemed strange, so I looked it up: “A person’s height also varies over the course of the day, by an average of 19 mm (¾ in), gradually shrinking as the spine compresses over the course of a day, and stretching back out overnight (Tyrrell, et al. 1985).” (wikipedia). So I guess you should measure your height in the morning!

Also, the shortest adult male documented was 1 ft 10.5 inches, and lived ’till 40. Picture!