Today the US Institute of Medicine released a major report that weighs the scientific evidence behind breast cancer’s possible link to various environmental factors. The report, over two years in the making and conducted by independent experts sponsored by a breast cancer advocacy group, reaffirmed much of what is already known, and pointed up the need for more — and better targeted — research.
“We at the American Institute for Cancer Research (AICR) welcome this report, which echoes AICR’s advice to focus on factors that have been clearly and convincingly shown to lower breast cancer risk — factors like eating smart, staying lean, moving more — and, of course, avoiding tobacco,” said AICR’s Director of Research, Susan Higginbotham, PhD, RD. “We know that many people are worried about other factors like air pollution, cosmetics, cleaning products and plastic food containers, but as the IOM report shows, we do not have solid scientific evidence that these factors affect human cancer risk. More research is needed.”
Specifically, the report found consistent evidence that women can reduce their risk of breast cancer by:
- Avoiding unnecessary medical radiation (NOTE: The report states that women should not be deterred from routine mammograms, but caution against “overuse” of CT scans)
- Forgoing treatments for menopause that combine estrogen and progestin
- Limiting alcohol intake (AICR advises women, if they choose to drink, to limit themselves to 1 alcoholic drink per day)
- Minimizing weight gain (In fact, the link between overweight/obesity and post-menopausal breast cancer was a key finding of the AICR/WCRF Expert Report and its follow-up Continuous Update Project: Breast Cancer. AICR advises women to aim to be as lean as possible without becoming underweight.)
The AICR/WCRF Expert Report and its updates also concluded that regular physical activity (at least 30 minutes of moderate-intensity activity every day) was protective against post-menopausal breast cancer, the most common form of the disease.
The IOM report stressed the need for more research into the effects of various factors at different stages of life, because breast tissue seems to be more sensitive to environmental influences — for good or for ill — at specific stages of development and throughout life.
The role of life course on cancer risk is one of several key research questions identified by the AICR/WCRF Expert Report, as was the need for more and better research on potential links between environmental chemicals and cancer.
“The bottom line,” said AICR’s Higginbotham, “is to concentrate on what thousands of studies have shown: The small choices we make every day about what to eat and how much to move make a big difference. In fact, AICR estimates that if we all ate healthy, balanced diets, got regular physical activity and maintained a healthy weight, we could prevent 2 out of 5 cases of breast cancer in the US every year — that’s about 74,000 cases.”