Many Americans suffer from low Vitamin D levels, and a number of health problems have been linked to that situation. A new study has found that low Vitamin D levels is associated with an increased risk of premature death. The findings were published online on June 12 in the American Journal of Public Health by researchers at the University of California San Diego.
The investigators assessed the relationship between serum Vitamin D levels and death from any cause (all-cause mortality) in a meta-analysis. A meta-analysis is a compilation of data from a number of studies to clarify the findings. They searched biomedical databases from January 1, 1966, to January 15, 2013 for articles that assessed two or more categories of Vitamin D. They identified 32 studies and pooled the data.
They found that the increased risk for all-cause mortality comparing the lowest (0–9 nanograms per milliliter) to the highest (more than 30 ng/mL) category of Vitamin D was 1.9-fold higher for the lowest group. In addition, serum Vitamin D levels less than or equal to 30 ng/mL were associated with higher all-cause mortality than concentrations greater than 30 ng/mL.
The authors concluded that their findings agreed with a National Academy of Sciences report with the one exception that the cutoff point for all-cause mortality reduction in their analysis was greater than 30 ng/mL rather than greater than 20 ng/mL.
Take home message:
Due to its Sunbelt location, natural sunlight is plentiful most days of the year. However, excessive sun exposure ages the skin and increases the risk of skin cancer. Vitamin D supplements are inexpensive and readily available. Also, some food products such as milk and orange juice are fortified with Vitamin D. The current recommendations by the Institute of Medicine (IOM) are based on age:
Age 1-70 years: 600 IU daily
Age 71 years and older: 800 IU daily
Pregnant and lactating women: 600 IU daily
Serum Vitamin D levels of 20ng/mL is adequate, and levels higher than 50 ng/mL could have potential adverse effects