Vitamin D Associated with Lower Breast Cancer Risk

On , In Body
woman in sunlight; highlighting the risks of vitamin d deficiency

A recent study revealed that women with higher levels of serum vitamin D have significantly lower breast cancer risk.1

Vitamin D is technically not a vitamin. Rather, it’s a hormone that synthesizes in the skin and converts to its active form in the liver. Vitamin D has amazing health benefits, from lowering cardiovascular risk to lower autoimmune disease rates. Many people who lack sun exposure on a regular basis do not synthesize adequate Vitamin D as it requires UVB light from the sun. A combination of living in the northern hemisphere and a modern indoor lifestyle lends itself to low levels of vitamin D on a population scale.

The Study

In this specific study, data was combined and analyzed from two randomized controlled trials from Creighton University. More than 5000 women, over the age of 55 were selected, with a broad range of vitamin D levels.

The study saw that women with a level of vitamin D above 150 nmol/L had an 80 percent lower risk for breast cancer than those with a serum level of 50 nmol/L or lower. There was also a dose-response relationship of cancer incidence when serum vitamin D levels were between 50 and 150 nmol/L. In other words, the higher the vitamin D level, the lower the breast cancer risk.

Vitamin D Levels & All-Type Cancer Risks

The principal investigator, Joan M. Lappe, PhD, RN, has also seen similar correlations with all-type cancer risks and vitamin D levels. In a 2007 study, she found that women who took vitamin D and calcium over a four-year period were 60 percent less likely to develop any type of cancer than women taking placebos. In 2017, she found that vitamin D levels of 137 nmol/L had a 35 percent lower risk of all-type cancer than women with levels of 75 nmol/L.

The Test

The recommendations for vitamin D levels of 1000 IU/Day are still too low. The recommendations still are not up to speed with the research. Consider testing your vitamin D levels once for a baseline, and then one year later to assess how much your body requires to maintain good health and prevent disease. We all have different needs based on hormone transitions, stress, environment, genetic polymorphisms, etc. We offer in-house vitamin D testing for $100 so contact us today to set up an appointment.


  1. McDonnell SL, Baggerly CA, French CB, et al. Breast cancer risk markedly lower with serum 25-hydroxyvitamin D concentrations ≥60 vs <20 ng/ml (150 vs 50 nmol/L): a Pooled analysis of two randomized trials and a prospective cohort. Plos One, June 15, 2018.
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