Highly contested study links milk consumption to breast cancer

A new study on milk and breast cancer has made headlines in recent days. According to researchers at Loma Linda University of Health (United States), the consumption of dairy milk is associated with an increased risk of breast cancer in women. Posted inInternational Journal of Epidemiology, this study found that drinking a cup a day could increase the risk of breast cancer in women (up to 80% depending on the amount consumed). However, these results must be taken with tweezers, as they are controversial.

Are dairy products the cause of breast cancer in women?

According to the study, even reasonable consumption of milk can increase the risk of breast cancer in women. For Gary Fraser, first author of the article, the observational study gives “fairly strong evidence that milk or another factor closely related to milk consumption is a cause of breast cancer in women. Consumption of 1/4 to 1/3 cup of milk per day is associated with a 30% increased risk of breast cancer. By drinking up to one cup per day, the associated risk increased by up to 50%, and for those who drank two to three cups per day, the risk increased by another 70% to 80%.. “

Before being alarmed about milk consumption, it is necessary to put things in context. First, this study assessed the food intake of 52,795 American women for almost eight years. These women, whose average age was 57 and none of them had cancer. For the purposes of this survey, the researchers asked the participants to respond to food frequency questionnaires. They had to record their food intake for the past 24 hours, in addition to a standard questionnaire containing information on their family history of breast cancer, their physical activity, their consumption of alcohol, hormonal and other drugs, as well as their history. gynecological and reproductive and possible screenings for breast cancer.

When the study ended, 1,057 new cases of breast cancer were recorded during follow-up. If the number of breast cancer cases in this study may seem impressive at first glance, it should be put in perspective with the total sample (52,795). By doing the calculation, the women followed with breast cancer ultimately represent only 2% of the cohort, a figure far too low to see any correlation between the consumption of cow’s milk and the increased risk of breast cancer. . If milk was really a product to consume reasonably, other tests should be carried out to support these results, as Gary Fraser indicates:Dairy milk has certain positive nutritional qualities, but these must be weighed against other less useful possible effects. This work suggests that there is an urgent need for further research.“

Milk, a thorny subject

All the research teams which have already looked into the question of the advantages or disadvantages of milk, or even dairy products, arrive at different results. According to studies, the consumption of dairy products, such as yogurt for example, is beneficial in reducing the risk of breast cancer, or is even responsible for the occurrence of prostate cancer in men. The supposed benefits or harms of milk, a thorny subject, must be taken with tweezers as it is difficult to disentangle the true from the false. For the moment, the simplest is to consider that they are neither good nor bad for health.

–