News

Increased vitamin D serum levels possibly the most cost-effective means of reducing global mortality

July 28, 2011

A new study from the US has reckoned that doubling serum levels of 25­hydroxyvitamin D showed to be the “most cost-effective way to reduce global mortality”.

The paper assessed the presumable impact on mortality rates of increasing serum vitamin D levels from 54 to 110 nmol/L in six geopolitical regions around the world: Africa, the Americas, Eastern Mediterranean, Europe, Southeast Asia and Western Pacific (1). The author identified and considered major vitamin D sensitive diseases with incidence and mortality rates that are reduced by higher serum 25(OH)D levels: e.g., cancer, cardiovascular disease (CVD), diabetes mellitus, bacterial and viral infections, musculoskeletal diseases and neurological diseases. To make his calculation, he referred to a wide range of forms of evidence, including epidemiological studies as – what he considered to be – a reliable base. He adopted the mean serum level of 54 nmol/L for each global region for use in his study on the basis of a meta-analysis of cross-sectional studies on global serum 25(OH)D status. The mortality rates for the various regions were obtained from World Health Organization (WHO) data from 2004. He calculated a reduction in the mortality rate for each region on the basis of death rates and vitamin D dose-response relations. The author postulates all-cause mortality rates dropping to a range of between 7.6% for African females to 17.3% for European females.

The study identified strong evidence that vitamin D intake can reduce mortality in the case of many diseases: e.g., CVD, respiratory infections and diseases, some cancers, multiple scleroses, falls and fractures and diabetes. For diabetes type II, the growing evidence for risk reduction with vitamin D was confirmed recently by a new review (2). This included eight observational studies and eleven randomized controlled trials. The meta­analysis of the observational studies showed that risk of diabetes type II decreased by 13% with vitamin D intake of >500 international units (IU) per day compared with a daily intake of <200 IU.

The author of the aforementioned study stated the several ways to raise serum 25(OH)D levels among the population: to increase food fortification (although, he points out that it is difficult to provide a high enough dosage), to make vitamin D supplements more readily available (although, probably not everybody at risk would take them) and to promote production of vitamin D from UVB-radiation (weighing the adverse effects against the positive health effects). He argued for more agreement between health policy makers; saying, “vitamin D has many health benefits and that society would benefit from higher levels” if there was a move “to implement policies to increase serum 25(OH)D levels at the national or regional level”.

References

  1. Grant W.B. An estimate of the global reduction in mortality rates through doubling vitamin D levels. European Journal of Clinical Nutrition 2011.
  2. Mitri J. et al. Vitamin D and type 2 diabetes: a systematic review. European Journal of Clinical Nutrition 2011.