Dairy products and ovarian cancer risk

Women consuming more than 2 glasses of milk, or high amounts of dairy products in their diet everyday, have higher risk of serous ovarian cancer.Serous epithelial cancer is a type of ovarian cancer that originates from the cells lining the outer surface of the ovary. Most cases of ovarian cancer originate from these cells.Researchers from the Karolinska Institute in Stockholm followed 61,084 women between the ages of 38 and 76 for an average of 13.5 years. Women kept a record of how often they consumed milk, yoghurt, cheese, ice cream or butter. None of the women had a history of cancer at the outset of the study.

About 266 women developed invasive epithelial ovarian cancer during the study period and 125 were diagnosed with the serous ovarian cancer. Researchers found that women who drank at least two glasses of milk or consumed at least four daily servings of dairy products were twice as likely to develop serous epithelial ovarian cancer as compared to those who consumed less than two servings of dairy products a day.

The findings suggest that high intakes of lactose and dairy products, especially milk, may increase the risk of serous ovarian cancer.
Though it remains unclear as to why extra dairy products increase the risk of ovarian cancer, one theory suggests it may be associated with lactose, a sugar found in dairy products. Future studies are needed to study ovarian cancer subtypes separately.