Is dairy linked to cancer?

Woman drinking milk

This article provided by Ashlyn Dau, MMN, RDN, LMNT

Cancer is a complex topic that includes more than 100 diseases. Research studies continue looking for answers to discover what may contribute to or cause cancer to develop in the first place.

While online searches reveal differing opinions (making ongoing research essential), we know that the nutrients found in dairy are vital for many aspects of health and well-being.

Can dairy cause cancer?

Dairy products are a multifaceted group of foods. Because the makeup of dairy varies by region, it makes evaluating possible associations with disease risk difficult. To date, no clear evidence shows that dairy causes cancer.

Based on a systematic review, the World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) report conclude:

  • A strong probable association between milk intake and a lower risk of colorectal (bowel) cancer
  • Limited evidence between diets high in calcium and increased risk of prostate cancer
  • Limited evidence of an association between milk intake and a lower risk of bladder cancer 

While valid research backs up these findings, the evidence is mixed or lacking for other cancer types.

What about dairy and breast cancer?

Looking at the larger body of research, including studying a broader population, the comprehensive AICR and WCRF breast cancer report found no evidence linking dairy or dairy milk to increased breast cancer risk. Instead, the AICR and WCFR report found limited evidence that dairy intake lowered the risk of pre-menopausal breast cancer, and high calcium intake lowered post-menopausal breast cancer. This report analyzed 119 studies, data on 12 million women and 260,000 breast cancer cases.

In addition, certain studies suggest that yogurt and cheese consumption may lower ER- (estrogen negative) breast cancer risk. Findings also conclude that it’s unlikely that eating dairy or foods with calcium affects the risk for common types (hormone positive – ER+) of breast cancer.

Is dairy good for patients with cancer?

It’s common for many cancer survivors to lose bone strength from treatment. With lower bone strength, a person may be more prone to breaking bones or developing osteoporosis (weak and brittle bones). Along with exercise, essential nutrients like calcium, protein and vitamin D found in dairy products are vital to helping regain bone strength.

Dairy is packed with nutritional benefits

Besides the cancer types calcium and dairy may benefit, dairy intake has numerous additional advantages, including:

  • Building strong bones and teeth and maintaining bone density
  • Lowering blood pressure
  • Calcium, protein, vitamin D and other nutrients that support gut health
  • Source of protein that helps build and repair muscle
  • Other essential vitamins and minerals like potassium and phosphorous

The USDA recommends including three servings of dairy daily. Generally, one cup of milk, yogurt, or one to 1 ½ ounces of cheese is considered one serving of dairy. Choose low-fat, low-sugar dairy because it can help maintain a steady weight and lower the risk of developing cancer due to being overweight or obese.

Examples of these healthy dairy sources include:

  • Skim or low-fat (1%) milk
  • Skim or low-fat (1%) cottage cheese
  • Low-fat yogurt (read the label for added sugars)

If you’re unable or don’t want to consume dairy products

Need to avoid dairy due to an intolerance or allergy? Find other options that provide a range of nutrients similar to what dairy offers. Options include plant-based milk, calcium-fortified juices, canned fish, tofu and dark leafy greens. Read the label on plant-based milk to check protein and calcium content. Often oat, almond, or rice milk are low in protein and may not have calcium added in. Fun fact: Soy milk has the most protein of the plant milks and the same amount as cow milk at eight grams per cup.

Calcium-rich foods versus supplements

Dairy foods contain higher amounts of calcium compared to other foods. Try to get your essential nutrients through your diet before supplementation, as food sources provide a whole package of nutrients that work together, often missed in supplements. Many different superfoods and nutrient-rich plant foods help boost calcium intake and protect against disease development.

Recommendations for calcium and vitamin D vary based on age. If you need help meeting your calcium goals, wonder about supplements, or have additional questions, contact a registered dietitian for guidance.

Are you concerned about your cancer risk? The Cancer Risk and Prevention Clinic can assess your risk and offer a personalized plan to prevent cancer. Call 402.559.5600 to schedule an appointment.