Your latest research update
Dairy and breast cancer risk
Dairy foods are everywhere: milk, yoghurt, cheese, butter, ice cream are only some of them. Each type can be also grouped in terms of their fat content - like fat-free milk, low-fat yoghurt, etc. What’s more, they also come in different forms – here are some less common examples:
- Powdered milk
- Kefir milk
- Whey milk
- Clarified butter
- Cream cheese
- Lassi yoghurt
- Frozen yoghurt
- …
Dairy products have been the subject of much research worldwide, with significant parts of that focusing on cancer. Recently, a new study was published from US-based researchers at the Department of Cancer Prevention and Control at Roswell Park Cancer Institute in Buffalo, NY. The study focused on how consumption of dairy can affect risk for breast cancer, and was based on more than 3,000 women (most of who had been diagnosed with breast cancer).
Is Dairy good or bad?
According to the published research findings, high total intake of dairy was associated with 15% lower risk for breast cancer. This was calculated after some factors were adjusted for (like age, body-mass index (BMI), menopausal status and family history of breast cancer).
Note that “high intake” was considered to be 42 servings per month or more (low intake = less than 14 monthly servings).
What raises breast cancer risk?
While Dairy is beneficial overall, scientists discovered that cheese had an opposite effect when consumed in high quantities. More specifically, they identified American, cheddar and cream cheese to be linked with a 53% increased risk. The other types of cheese analysed (which did not show such correlation) were low-fat cheese, ricotta and cottage cheese.
The bright side
Yoghurt provides compounds normally not found in fluid milk - like probiotics and prebiotics. This may be one of the reasons that researchers identified a more hopeful relationship in dairy and breast cancer risk through yoghurt. More specifically, women who consumed high amounts of yoghurt were found to have 39% lower risk of developing breast cancer.
Mediterranean diet: as good as expected?
You have probably heard a lot about the “Mediterranean diet”: fruits, vegetables, whole grains, beans, nuts, legumes, olive oils – as well as herbs and spices form its foundation. It also encourages eating fish, seafood, poultry, eggs and cheese more often than red meat.
As for the benefits, most of the time they have to do with our hearts: it can lower our “bad” cholesterol (LDL) and reduce our risk for cardiovascular episodes. But how does it affect cancer risk?
Dutch study with 62,573 women over 20 years
A study was conducted in the Netherlands, focusing on women post-menopause, aged 55-69. They estimated how closely these women adhered to the Mediterranean Diet, and followed them for any diagnosis of breast cancer.
The findings were clearer in one type: Mediterranean Diet was found to reduce the risk of oestrogen-receptor negative (ER-) breast cancer by 40%.
The risk for ER+ breast cancer, and breast cancer overall, was lower as well among women following this diet; however, this correlation was not as strong, according to scientists as described in the publication.
What does this mean?
While researchers highlight the need for more studies on this topic, they indicate that given the challenges of ER- breast cancer, such information could help prevent it. Furthermore, it is important to get more clear research data on how Mediterranean Diet affects those of us already diagnosed with breast cancer.
Soy foods reduce breast cancer mortality for some women
The impact of foods containing soy on breast cancer is one of the most frequently debated breast cancer nutrition topics. In fact, the nature of soy’s compounds and their relationship with hormones, have triggered endless discussions in absence of solid research evidence.
Isoflavones under study
More than 6,000 women with breast cancer were included in the study of foods containing “isoflavones”, oestrogen-like compounds contained in soy food. The women had previously been diagnosed with breast cancer of different types, and were followed up for a median of almost 10 years.
The results showed that higher consumption of isoflavones was associated with a 21% decrease in mortality rate – but only in two groups:
- women with hormone-receptor negative cancers
- women who had not been treated with hormonal therapy (e.g. Tamoxifen).
Your Next Steps
How has your nutrition been lately? Are you closer to a “Mediterranean diet”? What about consumption of dairy and soy foods?
Go back to your Timeline page and complete any Next Steps!