From left-skewness to symmetry: how body-height distribution among Swiss conscripts has changed shape since the late 19th century

Ann Hum Biol. 2015;42(3):260-7. doi: 10.3109/03014460.2014.942366. Epub 2014 Aug 26.

Abstract

Background: It is generally accepted that height distribution in modern populations is nearly symmetrical. However, it may deviate from symmetry when nutritional status is inadequate. Aim and subjects: This study provides an analysis of changes in the shape of the height distributions among Swiss conscripts (n = 267,829) over the past 130 years based on a highly representative, standardized and unchanged data source.

Results: The analysed distributions from the 1870s-1890s conscription years are markedly left-skewed (-0.76 to -0.82), with short and very short men significantly over-represented. Standard deviation is 7.7 cm. In particular, the left tails of the late-19th- and early-20th-century distributions are very heavy. In the first half of the 20th century the first signs of a diminution of the heavy left tail are observable, by the 1970s the phenomenon disappears and height distribution becomes symmetrical; standard deviation is now 6.5 cm.

Conclusion: The relatively strong left-skewness during the late 19th and early 20th centuries may have been due to the interaction of a number of causes, chiefly malnutrition, a wider range in physical development at age 19 and widespread iodine deficiency.

Keywords: Anthropometric history; distribution; iodine deficiency; malnutrition; stature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Height*
  • Humans
  • Male
  • Military Personnel*
  • Nutritional Status*
  • Switzerland
  • Time Factors
  • Young Adult