Vitamin D deficiency flagged as a major concern in South Asia

Strategies to improve vitamin D status are essential, say experts; global vitamin D maps in development

Bone health experts attending the 1st Asia-Pacific Osteoporosis Meeting in Singapore this week have flagged vitamin D deficiency as a major concern in the region, particularly in South Asia where the problem is especially severe and widespread across the entire population.

Dr. Nikhil Tandon, Professor of Endocrinology and Metabolism at the All India Institute of Medical Sciences of New Delhi, India highlighted the results of various studies which show severe deficiency across India and Pakistan in all age groups, as well as insufficiency in populations of South-East and East Asia. "A lack of exposure to sunshine, genetic traits and dietary habits are all factors which influence vitamin D levels. In certain regions, vitamin D deficiency can also be attributed to skin pigmentation and traditional clothing, as well as air pollution and limited outdoor activity in urban populations," he stated.

Vitamin D is primarily made in the skin when it is exposed to sunlight, with limited amounts obtained from food sources. However, in people with low sunlight exposure vitamin D is principally obtained from nutritional or supplemental sources. In the elderly, vitamin D deficiency is linked to reduced physical performance and increased risk of fall-related fractures. In children, severe vitamin D deficiency results in inadequate mineralization of bone, leading to growth retardation and bone deformities known as rickets. As well, there is evidence that children born to mothers who are vitamin D deficient during pregnancy may have reduced bone mass, which could in turn be a risk factor for osteoporosis later in life.

At a Vitamin D Roundtable held in conjunction with the meeting, nutrition and bone health experts discussed the importance of encouraging further studies on vitamin D status and risk factors in countries where data are scarce. The group is developing interactive vitamin D maps based on published data of 25(OH)D serum levels, the biomarker used to measure vitamin D status in the blood. Chair of the Roundtable, Professor Robert Josse, Professor in the Departments of Medicine and Nutritional Sciences at the University of Toronto, Canada commented, "The maps will track vitamin D levels by region and different population groups, giving a valuable overview of the prevalence of vitamin D deficiency around the world. The global maps are innovative tools that will help identify problem areas, encourage awareness and stimulate research studies. By facilitating global comparisons, the maps should provide an incentive for health authorities to implement strategies to improve vitamin D status in the population."