In a recent study published in PLOS ONE researchers reported that higher levels of vitamin D are associated with a decreased cancer risk.

Previous studies have linked a vitamin D deficiency with colon breast lung and bladder cancer. In this new study researchers have quantitated the amount of vitamin D to reduce cancer risk.

The researchers analyzed two previous studies. One was a randomized clinical trial of 1169 women while the other was a prospective cohort study of 1135 women. In the clinical trial the median blood serum level of 25(OH)D was 30 ng/ml and in the prospective cohort study it was 48 ng/ml.

The researchers found that the cancer rate decreased with increased vitamin D levels. Women with a vitamin D level of 40 ng/ml or greater had a 67% lower risk of cancer than women with levels of 20 ng/ml or less.

The recommended vitamin D blood level as well as the recommended daily allowance have been debatable over the past several years. In 2010 the Institute of Medicine (IOM) recommended a target of 20 ng/ml and an intake of 600 IU of vitamin D daily.

It is rare that I see patients with optimal vitamin D levels (over 50 ng/ml). I find that most people need about 4000-5000 IU of vitamin D daily to maintain normal healthy levels and approximately 8000-10000 IU daily for a few months to address a deficiency and get their vitamin D levels to an optimal range.

This new study confirms that reduced cancer risk is measurable at 40 ng/ml while additional benefits are seen at higher levels demonstrating an inverse relationship between vitamin D OH levels and risk of cancer.

The author states that increasing vitamin D levels to at least 40 ng/ml in the population would substantially reduce cancer incidence and associated mortality and improving vitamin D status is a key to prevention.

By Michael Jurgelewicz DC DACBN DCBCN