Human height

Human height or stature is the distance from the bottom of the feet to the top of the head in a human body, standing erect. It is measured using a stadiometer, in centimetres when using the metric system or SI system, or feet and inches when using United States customary units or the imperial system. In the early phase of anthropometric research history, questions about height measuring techniques for measuring nutritional status often concerned genetic differences. Height is also important because it is closely correlated with other health components, such as life expectancy. Studies show that there is a correlation between small stature and a longer life expectancy. Individuals of small stature are also more likely to have lower blood pressure and are less likely to acquire cancer. The University of Hawaii has found that the "longevity gene" FOXO3 that reduces the effects of aging is more commonly found in individuals of small body size. Short stature decreases the risk of venous insufficiency. When populations share genetic backgrounds and environmental factors, average height is frequently characteristic within the group. Exceptional height variation (around 20% deviation from average) within such a population is sometimes due to gigantism or dwarfism, which are medical conditions caused by specific genes or endocrine abnormalities. There are many pathological processes, both inherited and acquired, but the heights of many exceptional (>2 standard deviations from the mean) individuals are considered as natural variants. When no cause can be identified the deviation may be benign or pathological, and is considered idiopathic tall or short stature. When inheritance is concluded as the cause, as a natural variant, of exceptional height the term is familial tall or short stature. A variant related to familial stature, and sometimes used synonymously, and in some cases to distinguish height of a juvenile that...