To Reduce Risk of Ovarian Cancer, Get Calcium from Non Dairy Sources
Diet and healthy weight are both factors that you can control to reduce your risk for ovarian cancer. A new study focuses on calcium and vitamin D intake, and their effect on your overall risk.
Ovarian cancer is the fifth leading cause of cancer death among women in the United States. Risk factors for the disease include:
• Age – the risk of the disease increases with age with most cases developing after menopause.
• Obesity – women with a body mass index of 30 or greater are at a higher risk
• Family History – if ovarian, breast or colorectal cancer runs in your family, you may be at a greater risk if you have an inherited mutation in certain genes, including BRCA1 and BRCA2.
• Estrogen and Hormonal Therapy – some recent studies suggest that women using estrogens after menopause have an increased risk.
Another risk factor is diet. In a past study, women who follow a low-fat diet for at least 4 years showed a lower risk of ovarian cancer. This was especially true for women who ate a diet with an emphasis on plant foods, as the American Cancer Society recommends.
A more recent study from Rutgers Cancer Institute show that a diet high in calcium, but low in lactose may reduce the risk of ovarian cancer in African-American women. Past research has also found a link between dairy foods (the most common food source for calcium) and the risk of cancer, but the results have not always been consistent. Perhaps the key lies in the calcium source.
In this study, the investigators found that consumption of whole milk especially was significantly associated with an increased risk of ovarian cancer. Lower lactose foods, such as cheese and yogurt, were not found to have a significant association with increased risk.
Other good sources of low-lactose calcium include vegetables such as Chinese cabbage, kale and broccoli. Canned seafood where the bones of the fish are consumed (sardines, salmon) are also good sources. Some foods can be found to be fortified with calcium, such as cereals, tofu, and orange juice.
The team also studied Vitamin D. Increased sun exposure (vitamin D can be synthesized in the skin by being exposed to sunlight) may reduce ovarian cancer but Caucasian women only need about 5 to 15 minutes of mid-day sun to achieve an adequate amount of vitamin D while African American women may need as much as five to 10 times longer exposure due to skin pigment.
Obviously, this comes with some risk. The study's lead author, Bo "Bonnie" Qin, PhD says, "Because the benefits of increased sun exposure in African-American women may be offset by an increased risk of skin cancer, a combination of moderate sun exposure coupled with sufficient vitamin D intake from diet and supplements may be a safer solution for adequate vitamin D levels.”
Good food sources of vitamin D include, of course, fortified milk products. Other sources include fatty fish, egg yolks, fortified cereals, and some forms of mushroom.
Bo Qin, Elisa V Bandera et al. Dairy, calcium, vitamin D and ovarian cancer risk in African–American women. British Journal of Cancer, 2016; DOI:10.1038/bjc.2016.289
American Cancer Society
By Peter van der Sluijs (Own work), via Wikimedia Commons