Low Vitamin D Levels Increase Risk of Premature Death

Certain vitamins and minerals can play a critical role in our everyday health. A recent study conducted by researchers at the University of California, San Diego School of Medicine, found that inadequate levels of vitamin D can increase the risk of premature death. According to the study, published in the American Journal of Public Health, researchers found that participants with lower levels of vitamin D in their blood were up to two times more likely to die prematurely compared to those who had higher levels of the vitamin. 

"Three years ago, the Institute of Medicine (IOM) concluded that having a too-low blood level of vitamin D was hazardous," said Cedric Garland, DrPH, professor in the Department of Family and Preventive Medicine at UC San Diego and lead author of the study, in a news release. "This study supports that conclusion, but goes one step further. The 20 nanograms per milliliter (ng/ml) blood level cutoff assumed from the IOM report was based solely on the association of low vitamin D with risk of bone disease. This new finding is based on the association of low vitamin D with risk of premature death from all causes, not just bone diseases. "

For the study, researchers conducted a systematic review of 32 previously published studies that included data on 566,583 people from 14 countries. The average follow-up period for the study was about nine years, and the participants were an average age of 55 when their blood was drawn.

For this study in particular, researchers focused on a variant of vitamin D known as 25-hydroxyvitamin D that's mostly found in the blood.

Study findings revealed that about one half of the death rates were linked to vitamin D blood levels lower than 30 ng/ml. Unfortunately, an estimated two-thirds of the U.S. population carries levels lower than this.

"This study should give the medical community and public substantial reassurance that vitamin D is safe when used in appropriate doses up to 4,000 International Units (IU) per day," said Heather Hofflich, DO, professor in the UC San Diego School of Medicine's Department of Medicine reported in the press release. "However, it's always wise to consult your physician when changing your intake of vitamin D and to have your blood level of 25-hydroxyvitamin D checked annually. Daily intakes above 4,000 IU per day may be appropriate for some patients under medical supervision."