It is not new that there are many advocates for a completely dairy-free diet — no milk, yogurt, cheese and butter — arguing that this helps to stop cancer cells from growing, especially hormone-related cancers such as prostate, testicular and ovarian cancer (see “In the Matter of Milk“). But, what says the evidence?
Studies that investigate a link between dairy and cancer are inconclusive. Some research shows an increase in the risk of developing prostate cancer, while others show a possible protective role of dairy products on colorectal cancer risk. Consumption of dairy products has not been identified as a risk factor for breast or other types of cancer.
Despite evidence limitations, when it comes to milk and dairy, a recent article published in the Journal of the American College of Nutrition (JACN) states that “limiting or avoiding dairy products may reduce the risk of prostate cancer.” It was found that eating 35 grams of dairy protein (more than 4 cups of milk) increases the risk of prostate cancer by 32 percent. The authors acknowledge disadvantages of this recommendation and suggest other sources of calcium, including leafy vegetables, legumes and calcium-fortified foods.
As a food and nutrition professional, I believe that the recommendation of limiting dairy for cancer prevention can be risky and confusing for the press and for the public, especially given that dairy products are the main dietary source of calcium, an essential nutrient for bone health, and that they may even prevent colon cancer. I think that, for now, we should focus on a total diet approach and recommend a healthy, well-balanced diet (with more than 5 serving of fruits and vegetables daily). Calcium should be part of that diet, and milk is an important source of calcium.
Read the complete list of cancer-reducing dietary suggestions published in the JACN.