Editor’s Note: This article was published without including a quote from the Canadian Cancer Society. It has now been included. Global News regrets the omission.
Researchers tracked the dairy intake of 52,795 North American women for nearly eight years. All were cancer-free when the study began, but by the end, researchers recorded 1,057 new incidents of breast cancer.
“Consuming as little as one-quarter to one-third of a cup of dairy milk per day was associated with an increased risk of breast cancer of 30 per cent,” said researcher Dr. Gary Fraser in a press release.
Drinking up to one cup of dairy milk was associated with a breast cancer risk of 50 per cent, and drinking two to three cups per day increased a person’s risk by up to 80 per cent in some cases. The fat content of the dairy milk did not appear to affect the results.
In the study, a person’s family history, physical activity, alcohol consumption, medication use and reproductive and gynecological history were also taken into consideration.
Researchers also looked at soy milk, but no association with an increased breast cancer risk was found.
Roughly 75 per cent of dairy cows providing milk in modern dairy production are pregnant, according to researchers, which could be the reason for the increase in risk.
The study is “very strong,” according to Wendy Demark-Wahnefried, a professor of nutrition sciences and senior scientist with the O’Neal Comprehensive Cancer Centre at the University of Alabama Birmingham.
The results of this study prove that more research needs to be done — especially because milk is still widely regarded as an important part of a balanced diet, said Demark-Wahnefried.
The current U.S. dietary guidelines recommend three cups of milk per day for adults. In contrast, the Canadian food guide was updated in 2019 and dairy intake was de-emphasized relative to the prior version.
When it comes to drinks, the Canadian food guide recommends making water your beverage of choice.
Doctors will still often prescribe more milk for women because of concerns about osteoporosis, a disease characterized by low bone mass and deterioration of bone tissue. It more commonly affects women.
“If you’re a woman … you do need to pick up that calcium,” said Demark-Wahnefried.
According to the Mayo Clinic, there are several foods other than dairy that can help with calcium levels. For example, soy and almond milk that has been fortified, tofu made with calcium sulfate, canned pink salmon with bones and greens like turnip, collard greens and kale.
If further research has similar results, the standard plan for preventing osteoporosis will need to be updated.
Despite the “compelling” results of the study, Demark-Wahnefried says women don’t need to avoid drinking milk until further research is done.
“There may be some other thing that’s going on that … they didn’t control for.”
Elizabeth Holmes, manager of health policy at the Canadian Cancer Society, agrees with Demark-Wahnefried.
“The study adds to the overall body of evidence looking at dairy consumption and cancer risk,” Holmes told Global News. “More research is needed to understand the link between dairy products and cancer risk before any conclusions can be made.”
In their large systematic review of the evidence, said Holmes, the World Cancer Research Fund concluded that dairy products probably protect against colorectal cancer and there is limited suggestive evidence about it decreasing the risk of breast cancer or increasing the risk of prostate cancer.
“Eating well is an important part of reducing your cancer risk,” she said. “The Canadian Cancer Society encourages Canadians to follow Canada’s Food Guide and eat a variety of healthy foods every day.”
Choosing an alternative
A 2018 study from McGill University looked at the four most-commonly consumed types of plant-based milk drinks — almond milk, soy milk, rice milk and coconut milk — and compared their nutritional values to those of cow’s milk.
They found that after cow’s milk, which is still the most nutritious, soy milk was the “clear winner.”
In second was rice milk, with coconut and almond milk bringing up the rear. Here, researchers laid out the pros and cons of each option.
- Soy milk has been a substitute for cow’s milk for four decades and had the most balanced nutritional profile of the four milks included in the study.
- It is also widely consumed for the health benefits offered from the phytonutrients present in the milk. Known as isoflavones, these phytonutrients have anti-carcinogenic properties which can help prevent or delay cancer.
- However, some dislike the ‘beany flavor’ and there is concern about the presence of anti-nutrients (substances that reduce nutrient intake and digestion).
- As well as being lactose-free, rice milk can also be a good alternative for patients with allergy issues caused by soybeans and almonds.
- Its sweet taste makes it more palatable.
- However, it contains relatively little nutrition and there are also concerns about the high carbohydrate count.
- The consumption of rice milk without proper care can also result in malnutrition, especially in infants.
- Consumption can help reduce levels of harmful low-density lipoproteins (bad cholesterol) that are associated with cardiovascular diseases.
- It contains few calories, but most of them are from fat.
- It also contains no protein, and nutritional values are reduced if stored for over two months.
- Almonds have a high content of monounsaturated fatty acids (MUFA) that are considered helpful in weight loss and weight management.
- MUFA also helps in reduction of low-density lipoprotein (bad cholesterol).
- However, other complementary sources of food are needed to provide other essential nutrients.
— With files from AFP/RelaxNews