Tuesday April 29, 2014 (foodconsumer.org) -- A review released in British Medical Journal suggests that vitamin D deficiency may raise the risk of death from various diseases including cardiovascular disease and cancer.

Rajiv Chowdhury from University of Cambridge in Cambridge, UK and colleagues conducted the study and found higher serum vitamin D was associated with reduced risk of death from various chronic diseases like cardiovascular disease and cancer. 

Many previous studies have indicated that maintaining a sufficient concentration of circulating 25-hydroxyvitamin D in the blood may cut the risk of death from many diseases.  The current systemic study meta-analyzed the data from 73 cohort studies and 22 randomized controlled trials and confirmed the link between death risk and vitamin D deficiency.

The primary prevention observation studies show that people whose circulating 25-hydroxyvitamin D was in the bottom third distribution at baseline were 13%, 14%, 30% and 35% more likely to die from cardiovascular disease, cancer, non-vascular and non-cancer diseases, and all causes, respectively, compared with those whose vitamin D levels were in the top third of the vitamin D distribution.

The observational studies indicated risk of death was higher among those with lower baseline use of vitamin D supplements.

And randomized controlled trials revealed all-cause mortality was 11% lower among those using vitamin D3 supplements but somehow 4% higher among those using vitamin D supplements at baseline.  

Vitamin D2 supplementation was linked to higher risk of mortality when it was used in a lower dose for a shorter period while vitamin D3 supplementation was consistently associated with lower risk even when various groups with different chracteristics were studied together.

The researchers concluded "Evidence from observational studies indicates inverse associations of circulating 25-hydroxyvitamin D with risks of death due to cardiovascular disease, cancer, and other causes."

They also concluded "Supplementation with vitamin D3 significantly reduces overall mortality among older adults."

Vitamin D3 is readily available as a dietary supplement.  It can be purchased at local health stores or over the Internet.

Vitamin D deficiency has been linked to more than 100 health ocnditions including heart disease, cancer, depression, diabetes mellitus.  Previous studies suggest that maintaining a high level of serum vitamin D can decease the risk of breast cancer by more than 70%.

Exposure to sunshine is the way most people get vitamin D.   At the hottest hours of the day in Summer, exposure of bare hands and face to sunlight for 15 to 20 minutes can make a sufficient amount of vitamin D for a day.  (David Liu)