Questions about dairy and cancer are common, and the focus of this article is the effect of dairy products (like cow’s milk, cheese, yogurt, etc.) on the chances of getting cancer and cancer survivorship.  

What Research Shows about Dairy and Cancer Risk

The research on dairy and cancer shows mixed results. For example, there is strong research that dairy intake lowers the risk of colorectal cancer. On the other hand, some studies show dairy products may increase the risk of prostate cancer.

This doesn’t mean people with colorectal cancer should have more dairy while those with prostate cancer need to avoid it. It simply highlights the need for additional research and the importance of looking at themes instead of just one or two studies.  

If the research is inconclusive, what’s recommended in terms of dairy?  

We don’t yet have a clear picture of how dairy products affect every cancer individually. And even the differences between how dairy may affect colorectal and prostate cancer still need more research to be confirmed.  

Staying Up to Date about Dairy and Cancer

The most current research-based conclusions come out of the American Institute for Cancer Research (AICR)'s endeavor called the Continuous Update Project (CUP). This is a global effort amongst cancer experts to continuously review new research on cancer and lifestyle factors and issue updated recommendations whenever strong enough data emerges to change current guidelines.   

Research about Dairy Intake after a Cancer Diagnosis

Total dairy intake including yogurt, cheese, and skim/low-fat milk does not impact cancer survival, with one possible exception being prostate cancer. Limited evidence has found worse outcomes with higher intakes of dairy (400 grams/day) in those with prostate cancer, but this association isn’t clear for all types of prostate cancer.  

Action Steps to Take to Determine if Dairy is Right for You

As mentioned before, the CUP is a reputable resource to find the latest information specific to different types of cancer. 

Overall, the evidence so far does not suggest most people need to avoid dairy. Eliminating dairy products has not been shown to prevent or impact the overall prognosis for most cancers.  

If you’re at risk for or have been diagnosed with prostate cancer, talk with your care team to determine what types and quantities of dairy are best for you. When it comes to prostate cancer, remember full-fat dairy products (like whole milk) consumed frequently (several times a day) seem to pose the greatest risk.  

Dairy Alternatives

Some people choose not to have dairy for personal reasons. 

If you’re avoiding dairy, you can substitute with plant-based milks, such as soy milk and almond milk. If possible, choose unsweetened versions of these dairy alternatives whenever you can. If you’re relying on these foods for calcium intake be sure to buy calcium-fortified versions.  

Talk with your Iris Care Team if you have additional questions about dairy.