Human height can be changed by many factors. Since the development of modern medicine and plentiful food in the developed world average height has increased dramatically. Nutrition is the most important factor in height, and height records from military records and other documents can be used to quite accurately compare nutrition in various eras. Evidence has shown that height decreased in Britain in the early nineteenth century, before beginning its long increase around mid-century. Increase in height has not been constant, however. The European Dark Ages were an era of considerable height with men of above six feet (183 cm) considered unremarkable. In Europe human height reached its nadir at the start of the nineteenth century. The average height in Napoleon's army was about five feet (152 cm). Until the general rise in human health the general trend was as urbanization increased height declined.
Americans were far taller in the nineteenth century, the tallest in the world. However since the Second World War the height of Europeans have grown to surpass Americans by a fair margin, and has shown no sign of slowing. For instance the Netherlands was in the late nineteenth century a land renown for its short population, but today it has one of the tallest averages in the world with men averaging 6'0" (182.5 cm) tall. Average height in impoverished Vietnam and North Korea remains very small (5'4"/162.5 cm and 4'11"/150 cm respectively, for young men), especially in contrast to the extreme growth occurring in surrounding Asian populations with higher standards of living (young South Koreans are about a foot taller than their North Korean counterparts, on average).
Height has important social ramifications. For men shortness is often a disadvantage with women finding short men less attractive and other men less likely to respect them. For instance taller politicians have a tendency to win elections. Studies have found taller men marry earlier and earn higher wages. (However, some studies suggest that it is not adult height but rather the usually-correlated height during adolescence that is the determinative factor, suggesting that it is the impact of height on self-image that is operative.) It is almost the opposite for women where great height can be seen as unattractive.
Height can also play a role in sports. For most sports, height is useful as it affects the leverage between muscle volume and bones towards greater speed of movement. It is perhaps most valuable in basketball and volleyball where extreme height is a great advantage. In some sports such as horse riding and gymnastics a compact frame is far more valuable.
The study of human growth is known as axiology. Growth and height have long been recognized as a measure of the health and wellness of individuals, hence part of the reasoning for the use of growth charts. Genetics is a major factor in determining the height of individuals, though it is less influential in regard to populations. Average height is increasingly used as a measure of the health and wellness of populations. This is attributed as a significant cause for the trends of increasing height for egalitarian populations where medical care and proper nutrition are more equally distributed. Diet, exercise, fitness, pollution exposure, sleep patterns, and climate are other possible factors.
The relationship between genetics and environment is uncertain. Certainly there are substantial relationships in the general heights of biological families; and the heights of parents and family are a fairly good predictor for the height of their children. However, as cited, there is strong environmental influence as well. Asian populations were once thought to be inherently shorter, though it now seems that humans as a species probably have a similar genetic height potential, and it is clear that genotypic size has not yet been realized.
Country Average Male Height Population
Netherlands 182.5 cm 16,318,199
Denmark 181.5 cm 5,413,392
Switzerland 180.5 cm 7,450,867
Germany 180.2 cm 82,424,609
Croatia 180.0 cm 4,496,869
Norway 180.0 cm 137,253,133
Sweden 179.6 cm 8,986,400
Iran 178.7 cm 67,503,205
Austria 178.2 cm 8,174,762
Finland 178.2 cm 5,214,512
Czech Republic 178.0 cm 10,246,178
Romania 178.0 cm 22,355,551
South Africa 177.4 cm 42,718,530
Zimbabwe 177.2 cm 12,671,860
Australia 177.0 cm 19,913,144
Canada 177.0 cm 32,507,874
United Kingdom 177.0 cm 60,270,708
Greece 176.8 cm 10,647,529
France 176.6 cm 60,424,213
Ukraine 176.5 cm 47,732,079
Iraq 176.3 cm 25,374,691
Lebanon 176.2 cm 3,777,218
Ireland 176.1 cm 3,969,558
Zambia 176.0 cm 10,462,436
Russia 175.9 cm 143,782,338
Belgium 175.6 cm 10,348,276
United States 175.5 cm 293,027,571
Uzbekistan 175.4 cm 26,410,416
Poland 175.3 cm 38,626,349
Egypt 175.0 cm 76,117,421
New Zealand 175.0 cm 3,993,817
Senegal 175.0 cm 10,852,147
Portugal 174.6 cm 10,524,145
Saudi Arabia 174.6 cm 25,795,938
Argentina 174.4 cm 39,144,753
Uruguay 174.3 cm 3,399,237
Brazil 174.0 cm 184,101,109
Cuba 174.0 cm 11,308,764
Peru 173.8 cm 27,544,305
Thailand 173.6 cm 64,865,523
Spain 173.4 cm 40,280,780
Korea, South 173.3 cm 48,598,175
Paraguay 173.1 cm 6,191,368
Syria 173.0 cm 18,016,874
Chile 173.0 cm 15,823,957
Morocco 173.0 cm 32,209,101
Turkey 172.5 cm 68,893,918
Tunisia 172.3 cm 9,974,722
Colombia 172.3 cm 42,310,775
Algeria 172.2 cm 32,129,324
Mexico 171.8 cm 104,959,594
Cameroon 171.0 cm 16,063,678
Indonesia 170.0 cm 238,452,952
China 169.7 cm 1,298,847,624
Pakistan 169.3 cm 159,196,336
Japan 168.3 cm 127,333,002
Mongolia 168.0 cm 2,751,314
India 167.6 cm 1,065,070,607
Italy 165.6 cm 58,057,477
Philippines 165.0 cm 86,241,697
Korea, North 164.9 cm 22,697,553
Malaysia 163.5 cm 23,522,482
Vietnam 162.5 cm 82,689,518
Singapore 162.2 cm 4,353,893
Cambodia 160.0 cm 13,363,421
