254 Vitamin D & Breast Cancer [10 February 2014]

The recent visit to Rosetown of the snowmobilers raising money for breast cancer research inspired this week’s topic. While more research is always good, there is much that we have already learned from existing research that we aren’t taking full advantage of. One example is vitamin D’s role in breast cancer. Here are some recent study results gleaned from the Vitamin D Council’s website.

• A 2013 review from McGill University pooled data from 8 studies and found vitamin D deficiency was associated with increased recurrence of breast cancer and increased risk of death.
• A 2013 meta-analysis by Harvard researchers found a moderate reduction in risk of breast cancer with vitamin D levels in post-menopausal women but not in pre-menopausal women.
• A 2012 Mexican population-based case-control study found an inverse association between D levels and breast cancer risk (as D increases, risk decreases) in both pre and post menopausal women.
• Similar studies of women in Saudi Arabia (2013) and China (2013) also found an inverse association between vitamin D levels and breast cancer risk.

According to John Cannell MD of the Vitamin D Council, the difference in survival between women with low D levels (<20 ng/ml) vs. those with adequate levels (>30) are significant but not huge. Overall, the five-year survival rate increased from an average of 97.6% to 98.4% and the ten-year rate increased from 84.8% to 88.0%. Much of the ten-year increase in survival was from prevention of death from causes other than breast cancer, but the ten-year death rate specifically from breast cancer did fall from 8.3% to 4.5%.

Most of these were observational studies which do not prove a causal connection but there is no need to wait 10 years for more research before taking action. Whether you already have breast cancer or wish to prevent it, you don’t want to be vitamin D deficient! In the studies quoted above the benefits of D increased with increasing blood levels to about 35 ng/ml so you want to ensure your levels are at least that high. Cannell recommends maintaining 50 ng/ml for optimal health.

For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.