Ovarian cancer makes up approximately 3 percent of all cancers in women and a woman's chance of being diagnosed with ovarian cancer throughout her lifetime is about one in 71, according to the Ovarian Cancer National Alliance. Only 20 percent of ovarian cancers are detected at an early stage. Some research has shown a possible correlation between vitamin D levels and risk for ovarian cancer.
Vitamin D and Calcium
Low levels of vitamin D may increase risk of ovarian cancer in some women, according to a study published in the October 2010 issue of the "European Journal of Cancer." The study evaluated vitamin D levels prior to cancer diagnosis in more than 170 women with ovarian cancer compared to the same number of women without ovarian cancer and found that those with the lowest levels of vitamin D had the greatest risk for developing ovarian cancer. The researchers noted also that when calcium levels were considered, there was no increased protection at higher calcium and vitamin D levels than from either one by itself.
Geographical Location
Women who live in geographical locations that receive less sunshine may have increased risk for ovarian cancer, according to a study published in the November 2010 issue of the journal "Gynecological Oncology." In the study of over 7,200 women, ovarian cancer was as much as four times more likely in those with lower vitamin D levels living in low-sunshine areas. Additionally, genetic factors affecting vitamin D absorption may contribute to the increased risk in susceptible women.
Questionable Association
The "American Journal of Obstetrics and Gynecology" reported in its July 2010 issue on a study that found no overall risk for ovarian cancer with low vitamin D levels. In the meta-study -- a review of previously published research -- the authors found an equal number of studies that showed an association between vitamin D levels, sunshine levels and vitamin D consumption and ovarian cancer as those that showed no association between these presumed risk factors. While vitamin D consumption was low in all studies, the researchers concluded that vitamin D levels before diagnosis did not influence risk for developing ovarian cancer, in this study.
Slight Effect
A slight ovarian cancer risk reduction with higher vitamin D levels was found in a study published in the February 2011 issue of the journal "Gynecology and Oncology." From the review of 10 previously published studies, the authors concluded that a tentative association between circulating vitamin D levels and occurrence of ovarian cancer may exist. However, the difference was not statistically significant and further studies are warranted to clarify their results.
References
- "European Journal of Cancer"; Independent and joint effects of serum 25-hydroxyvitamin D and calcium on ovarian cancer risk: a prospective nested case-control study. Toriola AT; at al.; October 2010
- "Gynecologic Oncology"; Casting light on 25-hydroxyvitamin D deficiency in ovarian cancer: a study from the NHANES. Bakhru A; November 2010
- "American Journal of Obstetrics and Gynecology"; A systematic literature review of vitamin D and ovarian cancer. Cook LS;July 2010
- "Gynecologic Oncology";Meta-analysis: Circulating vitamin D and ovarian cancer risk. Yin L; February2011
