My physics teacher told us (while teaching the topic gravitation) that gravity has a effect on height of human body, he gave us following examples:
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The height of astronauts after coming back to earth is found to be increased slightly.
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The people living at equator (such as in west indies) are usually found longer than people living in polar countries (as value of $g$ differ at pole and equator). {This example seems quite interesting and I have a doubt in it}.
His examples were quite interesting and also confusing (as I am unable to get the reason behind them), but I suppose I can get the answer here. I hope for an answer which may describe the relation between gravity and height of a person.
Best Answer
The human body is somewhat elastic (a good property to have, otherwise we would break bones more frequently) and as with any elastic body it will tend to stretch or compress when subjected to a force. Gravity is such a force. When we stand upright, the force of gravity compresses us and makes us a little shorter. If we measured our height while hanging by our heels, the effect would be opposite and we would be somewhat taller.
As for the observation that people living at or near the equator tend to be taller than those living near the polar regions, I would doubt that that (if true) is due to gravity. The gravitational effect is probably too small to dominate over other factors such as genetics and nutritional effects.