Persons from different geographical regions differ, since their body dimensions (absolute dimensions) differ and the proportions (proportional dimensions) are distributed differently. Northern Europeans for example are generally particularly tall, whereas Southern Europeans tend to be shorter (see table below). However, sufficient data are not always available for every country. In this case it is preferable to base considerations upon the data for neighbouring or comparable countries than to dispense with considering the body dimensions completely.
| County / region | Northern Europe | Central Europe | South-east Europe | West Africa | Middle East | North America | Japan |
|---|---|---|---|---|---|---|---|
| P5 | 1710 | 1670 | 1660 | 1560 | 1620 | 1670 | 1630 |
| P50 | 1810 | 1770 | 1750 | 1670 | 1710 | 1790 | 1720 |
| P95 | 1910 | 1860 | 1850 | 1790 | 1800 | 1900 | 1820 |
Besides differing in their length dimensions, different populations also differ strongly in their circumferential dimensions.
The reasons for the regional differences in body dimensions are numerous. On the one hand, they are genetic in origin (for example owing to adaptation of human populations over the long term to different climatic conditions); on the other, they are strongly dependent upon socio-economic conditions. Populations living under favourable socio-economic conditions have become taller from generation to generation (secular trend), and in more recent years also fatter.