A report into the risk of women developing breast cancer and the consumption of dairy products has found that it depends on whether she is pre or postmenopausal.
The study, authored by Myung-Hee Shin and colleagues from the Harvard School of Public Health and Harvard School of Medicine in Boston, investigated more than 88,600 women about the milk and calcium intake in their diets, including whether they used calcium and vitamin D supplements (if so, how much they took). The researchers also looked at the type of diary product they consumed such as low-fat verses whole milk, how much high-fat food (cream, ice-cream, butter, etc), and fermented dairy (yoghurt, sour cream, etc) they ate.
Results indicated that low-fat dairy intake was linked to lower risk. They included the following:
- Dairy products did not have any effect on risk in postmenopausal women, however, there was a relationship between larger amounts of low-fat dairy intake and lower risk in premenopausal women.
- Calcium and vitamin D were not related to the risk of developing breast cancer in postmenopausal women, but decreased the risk in premenopausal women.
- Calcium supplement pills didn’t decrease the risk in postmenopausal women, but did in premenopausal women if they had a lot of calcium form their regular diet.
In this study, ‘intakes of dairy foods, calcium, or vitamin D were not associated with the risk of breast cancer among postmenopausal women’, wrote the author. ‘Among premenopausal women, however, most of the dairy-related variables were inversely related with breast cancer. That means the more dairy products premenopausal women consumed, the lower their risk of cancer’.
Researchers noted that just because a woman consumed high quantities of dairy products before menopause, which may lower her risk, doesn’t mean that her low-risk status will continue once she enters menopause.
They said, ‘the apparent association of intake of milk and its related nutrients with reduced risk of breast cancer disappeared quickly after menopause’.
It was not clear why milk and related nutrients should work differently in pre and postmenopausal women.
‘In conclusion, high intakes of dairy products, especially low-fat dairy and skim/low-fat milk, may be associated with a modest reduction in the risk of breast cancer in premenopausal women but not in postmenopausal women,’ researchers wrote.’Further study of the relationship between dairy product consumption and breast cancer is warranted, with a specific focus on premenopausal women,’ they concluded.
(Source: American Cancer Society)