British Journal of Nutrition

Systematic Review

A systematic review of vitamin D status in populations worldwide

Jennifer Hilgera1, Angelika Friedela2, Raphael Herra1, Tamara Rauscha1, Franz Roosa2, Denys A. Wahla3, Dominique D. Pierroza3, Peter Webera2 and Kristina Hoffmanna1 c1

a1 Mannheim Institute of Public Health, Social and Preventive Medicine, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 7-11, D-68167 Mannheim, Germany

a2 DSM Nutritional Products Limited, Kaiseraugst, Switzerland

a3 International Osteoporosis Foundation, 1260 Nyon, Switzerland

Abstract

Vitamin D deficiency is associated with osteoporosis and is thought to increase the risk of cancer and CVD. Despite these numerous potential health effects, data on vitamin D status at the population level and within key subgroups are limited. The aims of the present study were to examine patterns of 25-hydroxyvitamin D (25(OH)D) levels worldwide and to assess differences by age, sex and region. In a systematic literature review using the Medline and EMBASE databases, we identified 195 studies conducted in forty-four countries involving more than 168 000 participants. Mean population-level 25(OH)D values varied considerably across the studies (range 4·9–136·2 nmol/l), with 37·3 % of the studies reporting mean values below 50 nmol/l. The highest 25(OH)D values were observed in North America. Although age-related differences were observed in the Asia/Pacific and Middle East/Africa regions, they were not observed elsewhere and sex-related differences were not observed in any region. Substantial heterogeneity between the studies precluded drawing conclusions on overall vitamin D status at the population level. Exploratory analyses, however, suggested that newborns and institutionalised elderly from several regions worldwide appeared to be at a generally higher risk of exhibiting lower 25(OH)D values. Substantial details on worldwide patterns of vitamin D status at the population level and within key subgroups are needed to inform public health policy development to reduce risk for potential health consequences of an inadequate vitamin D status.

(Received July 12 2012)

(Revised March 08 2013)

(Accepted May 07 2013)

(Online publication August 09 2013)

Key Words:

  • Vitamin D;
  • Populations;
  • Public health

Correspondence

c1 Corresponding author: Dr K. Hoffmann, fax +49 621 383 9920, email kristina.hoffmann@medma.uni-heidelberg.de

Footnotes

  Abbreviations: 25(OH)D, 25-hydroxyvitamin D