For postmenopausal breast cancer, there’s a strong body of evidence that shows exercising reduces the risk. But cancer can take years to develop. A new study that may help explain the link now suggests that when young women jog and are aerobically active it causes changes in estrogen metabolism, which then plays a role in reducing later breast cancer risk.
The study, published in Cancer Epidemiology, Biomarkers & Prevention, is one of only a few clinical trials to focus on exercise and estrogen metabolism among younger women.
Study researchers wanted to focus on estrogen metabolism because the majority of breast cancers are related to the hormone estrogen. Research suggests that a higher lifetime exposure to estrogen increases a woman’s risk for breast cancer. Yet there are many forms of estrogen and they appear to play a different role in risk.
Lab studies have suggested that two of the forms, estradiol and estrone, play a role in cancer development. These forms of estrogen break down or metabolize into compounds and it’s the ratio of these metabolites that studies have suggested may influence breast cancer risk.
For this study, researchers randomly divided almost 400 sedentary young women into two groups: about half of the women were asked to exercise regularly and the others continued with their inactive lifestyle. All the women were premenopausal and the groups included women who were roughly the same age and weight. Continue reading
Dairy foods like ice cream, regular cheese and whole milk are high in fat and saturated fat, linked to an increased risk for heart disease. There is little evidence that total dietary fat affects cancer risk, but it is less clear whether specific high fat foods or types of fats affect cancer risk.
Now, a new study published in the Journal of the National Cancer Institute suggests that, for breast cancer survivors, consuming high fat dairy foods may be related to an increased risk of breast cancer mortality.
The researchers followed 1893 women diagnosed with early-stage invasive breast cancer who were enrolled in the Life After Cancer Epidemiology (LACE) study. The participants completed food frequency questionnaires, including how much dairy they consumed, when they entered the study and in 6 year follow-up surveys. In this study median follow-up was 11.8 years. Continue reading
Sweet potatoes, tomatoes, and the many other colorful fruits and vegetables high in carotenoids may reduce women’s risk of breast cancer, suggests a new analysis published last week.
The study was published in the Journal of the National Cancer Institute.
Carotenoids are a large group of phytochemicals that give our foods their red, orange, and yellow hues. Many dark green vegetables, such as kale and spinach, also contain plenty of these phytochemicals. Beta-carotene, lycopene, zeaxanthin and lutein are a handful of the well-studied carotenoids for their role in cancer prevention – and other health benefits, such as eye health. Continue reading