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 1,169 women, while the other was a prospective cohort study of 1,135 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 8000–10,000 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
Source: Sharon L. McDonnell, Carole Baggerly, Christine B. French, Leo L. Baggerly, Cedric F. Garland, Edward D. Gorham, Joan M. Lappe, Robert P. Heaney. Serum 25-Hydroxyvitamin D Concentrations ≥40 ng/ml Are Associated with >65% Lower Cancer Risk: Pooled Analysis of Randomized Trial and Prospective Cohort Study. PLOS ONE, 2016; 11 (4): e0152441 DOI: 10.1371/journal.pone.0152441