According to a new study, drinking dairy milk may increase women’s breast cancer risk. The association appears strong, and is even present in women who consume small quantities of milk. Dr. Gary E Fraser, the corresponding researcher, shared the following insight.
Consuming as little as 1/4 to 1/3 cup of dairy milk per day was associated with an increased risk of breast cancer of 30%. By drinking up to one cup per day, the associated risk went up to 50%. And for those drinking two to three cups per day, the risk increased further to 70% to 80%.
In light of their findings, Fraser raised concerns over the U.S. Dietary guidelines, which recommend the equivalent of three cups of milk per day.
Breast Cancer Risk Rises with Each Glass of Dairy Milk
This cohort study was conducted at Loma Linda University, and followed the dietary intakes of 52,795 North American women for about 8 years. The group included both pre- and post-menopausal women, but participants had a mean age of 57 years.
All of the women were initially cancer free and were screened for various control factors, including demographics, family history of breast cancer, physical activity, alcohol consumption, hormonal and other medication use, breast cancer screening, and reproductive and gynecological history.
By the end of the study, the group had 1,057 new breast cancer cases with a notable association to milk consumption. The researchers were able to conclude that the higher the intake of dairy calories and dairy milk, the greater the greater risk of breast cancer. And the type of dairy milk didn’t seem to matter. Full fat and reduced fat milks produced similar results.
The study group was also evaluated for soy intake, and the researchers found no clear associations between soy products and breast cancer. In fact, the data showed a “marked reduction in risk” associated with substituting soymilk for dairy milk.
These findings correlate with the recent Adventist Health Study that suggested vegans, but not lacto-ovo-vegetarians (who consume milk and eggs), have a reduced risk for female-specific cancers, like breast cancer.
 Gary E Fraser, Karen Jaceldo-Siegl, Michael Orlich, Andrew Mashchak, Rawiwan Sirirat, Synnove Knutsen, Dairy, soy, and risk of breast cancer: those confounded milks, International Journal of Epidemiology, dyaa007, https://doi.org/10.1093/ije/dyaa007
 Gary E Fraser, Michael Orlich, Vegetarian diets in the Adventist Health Study 2: a review of initial published findings, The American Journal of Clinical Nutrition, www.ncbi.nlm.nih.gov/pmc/articles/PMC4144107/
This post is for informational purposes only. It should not be construed as medical advice. Always consult a physician before undergoing any change in diet.