Vitamin D Deficiency and Insufficiency

Vitamin D deficiency has been linked to the pathogenesis of osteoporosis and hip fractures as well as other skeletal and non-skeletal disorders. Although there is ongoing debate as to the exact definition of vitamin D insufficiency, a 2009 report from the International Osteoporosis Foundation (IOF) Nutrition Working Group shows that regardless of whether it is defined at 50nmol/L or 75nmol/L, vitamin D status is seriously inadequate in large proportions of the population across the globe.

The review provides a global perspective of vitamin D status across different regions of the world and identifies common and significant determinants of hypovitaminosis D. Six regions of the world were reviewed—Asia, Europe, Middle East and Africa, Latin America, North America, and Oceania—through a survey of published literature.

The main risk factors for low vitamin D levels include older age, female sex, higher latitudes, winter season, darker skin pigmentation, less sunlight exposure, dietary habits, and the absence of vitamin D fortification in common foods. Further factors include the increase in urbanization, where people tend to live and work indoors, as well as cultural practices that tend towards sun avoidance and the wearing of traditional clothing that covers the skin. The severity of the problem in Middle East and South Asia arises from the combination of several of these risk factors.

These findings suggest that prevention strategies must be initiated at the national level - especially given the increasing ageing of populations in many regions of the world. National plans of action should encourage safe, limited exposure to sunlight and improved dietary intake of vitamin D, whilst considering fortification of foods as well.

Global vitamin D status and determinants of hypovitaminosis D (2009)

A. Mithal, D.A. Wahl, J-P. Bonjour et al. on behalf of the IOF Committee of Scientific Advisors (CSA) Nutrition Working Group. Global vitamin D status and determinants of hypovitaminosis D (2009) Osteoporosis International,  Vol. 20, Number 11 , 2009, p. 1807-1820. Read the complete report.

Download IOF Position Statement on Vitamin D in Older Adults (2010) (PDF, 98.6 KB)

Download regional reports on vitamin D status:

Asia (PDF, 387.7 KB)
Europe (PDF, 289.3 KB)
Middle East and Africa (PDF, 307.2 KB)
Latin America (PDF, 226.7 KB)
North America (PDF, 275.9 KB)
Oceania (PDF, 238.8 KB)