For starters, in a 2008 study reported by the American Cancer Institute, women with the lowest levels of Vitamin D at the time of their breast cancer diagnosis, had nearly double the risk of their disease progressing, as compared to women with “adequate” levels of Vitamin D. Does that mean women, without breast cancer, who are interested in preventing a metastasis (should they ever get breast cancer), take Vitamin D, and if so, how much?
Secondly, the same study said survival rates of women with estrogen receptor negative breast cancer, which is generally more aggressive, was not related to their Vitamin D levels. Other scientists are quick to say that while there is much published research on Vitamin D, and its relationship to breast cancer, the findings are debatable.
So what does this study mean for women who have, or do not have breast cancer? Many doctors ask patients if they take calcium and Vitamin D, but have any of your doctors ever ordered a blood test to check your level of Vitamin D? What are “adequate” levels of Vitamin D? Do most doctors even know how much this?
Here is what we do know about Vitamin D and breast cancer: If you take aromatase inhibitors, like Arimidex, it is especially important to get enough calcium and Vitamin D. As my oncologist says, calcium works in tandem with Vitamin D to keep our bones from “turning to mush.” It is also important to keep in mind that too much Vitamin D can be harmful, causing nausea, vomiting, constipation, weakness and changes in heart rhythm. If you are over 50, the Mayo Clinic recommends you take 400 to 600 IU a day, and that generally, the upper limit for Vitamin D is 2,000 IU a day.
In addition to Vitamin D in pill form, small amounts of Vitamin D are naturally found in oily fish like salmon, tuna and mackerel, plus some cereals, dairy products and orange juice are fortified with Vitamin D. So, be a smart shopper. Check labels, and if you have a choice, reach for products with added Vitamin D.
We also know sunlight is a natural way our bodies make its own Vitamin D. If, however, you carry one of the BRCA genes, too much sun may raise your risk for melanoma and other types of skin cancer. Even if you are not BRCA positive, long-term exposure to UV rays can cause skin cancer, plus it is aging. I would not lay out in the sun, like a big ole lazy lizard, and justify it by saying, “I’m getting my Vitamin D.” Whether you are out on a sunny or cloudy day, use sunscreen and reapply it often.
Then there is the debate about tanning beds vs. natural sunlight. Where does this all stop?