Having celiac disease increases your chances of developing certain other cancers, including non-Hodgkin's lymphoma. But what does it do to your chances of getting breast cancer?
It looks like there's good news for women with celiac disease: the condition seems to significantly lower your odds of developing breast cancer.
(Although the evidence is scantier, this may also be true for women with non-celiac gluten sensitivity see Gluten Sensitivity and Cancer Risk for the details.)
It's not completely clear why this protective effect occurs in celiac women, but it may be due to celiac's effects on your hormones women with celiac disease tend to get their periods later, enter menopause earlier, and generally have lower fertility levels. This could be a result of lower levels of circulating estrogen and progesterone, two hormones that have been linked to breast cancer.
See more on this: Celiac Disease Symptoms in Women
Studies Show Lower Levels of 'Female' Cancers in Celiacs
Several medical studies have identified a lower risk of breast cancer in women who have been diagnosed with celiac disease.
For example, a study published in 2004 in the British Medical Journal compared 3,095 women with celiac disease to 18,545 control subjects without the condition. The study found a rate of breast cancer in celiac women about 40% lower than the rate in the control subjects.
The researchers couldn't explain the results, but they speculated that certain unknown genetic, nutritional or environmental factors may protect people with celiac disease against breast cancer and certain other cancers. "By understanding the mechanism of protection in people with celiac disease, we may gain insight into the causes of breast cancer," they wrote.
In a second study, this one published in 2012 in the International Journal of Cancer, researchers used Sweden's national medical records to identify 17,852 women with celiac disease, estimated their expected risk of breast cancer, and then compared them to 88,400 similar control subjects.
That study also found women with celiac disease were significantly less likely to develop breast cancer; although the odds weren't as low as in the 2004 BMJ study, they improved beyond the first year past the women's diagnoses of celiac disease, the researchers said.
Lower Risk Extends to Ovarian, Endometrial Cancers
Women with celiac disease may also have lower risks of ovarian and endometrial cancers, two other forms of female reproductive cancers.
In addition to breast cancer risk, the 2012 Swedish study also looked at how many women with celiac disease developed ovarian and endometrial cancers. The researchers found much lower levels of both cancers in women with celiac disease when compared to control subjects.
It's possible that lower levels of circulating female hormones, including estrogen and progesterone, could lead to lower levels of those two cancers in addition to breast cancer, the researchers speculated. It's also possible that something in the genetic makeup of women with celiac disease leads somehow to the decreased risk, they said.
What Does This Mean for Women with Celiac Disease?
Although more research needs to be done to determine why women with celiac disease have lower rates of breast, ovarian and endometrial cancers, it's still good news, especially since rates of other forms of cancer (notably, non-Hodgkin's lymphoma) are higher in people who have celiac.
Still, having a lower risk of breast cancer (or ovarian cancer or endometrial cancer) than the overall population doesn't guarantee you won't develop the disease in each of these studies, some celiac women did develop these cancers. Therefore, you might do well to talk to your doctor about your overall risk of breast cancer, and other ways you may be able to lower your risk for the disease (see more on this in Breast Cancer Prevention).
Learn more about your overall cancer risk: Celiac Disease and Cancer
Ludvigsson J.F. et al. Reduced risk of breast, endometrial and ovarian cancer in women with celiac disease. International Journal of Cancer. 2012 Aug 1;131(3):E244-50. doi: 10.1002/ijc.26454. Epub 2011 Dec 14.
West J. et al. Malignancy and mortality in people with coeliac disease: population based cohort study. British Medical Journal. 2004 Sep 25;329(7468):716-9. Epub 2004 Jul 21.