A new review from Germany reports that of almost 200 population-based studies worldwide more than 37% report that inadequate blood vitamin D levels are wide-spread.
The systematic review analyzed data on vitamin D supply from more than 168,000 people across 195 studies conducted in 44 countries (1). The analysis showed that 37.3% of the studies reviewed reported mean serum vitamin levels, measured by 25-hydroxyvitamin D values, to be below 50 nmol/L, a value considered inade-quate by health authorities worldwide. The vitamin D values were higher in North America than in Europe or the Middle-East. Age-related differences were observed for the Asia-Pacific and Middle East regions, but not elsewhere. Sex-related differences were not observed in any region.
The researchers commented that although vitamin D deficiency is associated with osteoporosis and is thought to increase the risk of cancer and cardiovascular disease, data on vitamin D status at the population level and within key subgroups are limited. The substantial heterogeneity between the reviewed studies within each region precludes drawing conclusions on overall vitamin D status at the population level.