Every woman wants to know what she can do to lower her risk of breast cancer. Some of the factors associated with breast cancer – being a woman, your age, and your genetics, for example – can’t be changed. Other factors – being overweight, lack of exercise, eating unhealthy food – can be changed by making choices. By choosing the healthiest lifestyle options possible, you can empower yourself and make sure your breast cancer risk is as low as possible.
Still, it may seem overwhelming to try and change so many things at once. A study looked at ways to reduce breast cancer risk that apply to all women and explains how much certain prevention strategies can reduce risk.
The study was published in the May/June 2014 issue of CA: A Cancer Journal for Clinicians. Read “Priorities for the primary prevention of breast cancer.”
Overall, the researchers estimated that more than half of all breast cancers could be prevented if women adopted healthy behaviors and if women at high risk for breast cancer took medicines to reduce that risk.
To help women decide which behaviors they might want to change, the researchers prioritized breast cancer prevention strategies.
Get regular exercise and maintain a healthy weight throughout life: Exercise and being at a healthy weight can reduce the risk of breast and other cancers. Still, more than 66% of U.S. adults are overweight or obese and more than 50% don’t get enough exercise. Research has shown that gaining weight after age 18 is linked to a higher risk of postmenopausal breast cancer that is directly related to the amount of weight gained. This higher risk is because fat cells make estrogen; extra fat cells mean more estrogen in the body, and estrogen can make hormone-receptor-positive breast cancers develop and grow.
At the same time, overweight postmenopausal women who lost 22 or more pounds and kept it off reduced their breast cancer risk by more than 50% compared to women who didn’t lose weight.
Research also has shown that regular exercise reduces breast cancer risk for both pre- and postmenopausal women. The American Cancer Society and many doctors recommend women exercise 4 to 5 hours per week at a moderate intensity level. (Brisk walking is moderate intensity exercise.)
Limit alcoholic beverages: Research suggests that drinking more increases breast cancer risk. Each 10-gram-per-day increase in alcohol consumption leads to a 7% to 10% increase in breast cancer risk (an average drink has about 14 grams of alcohol). Even light drinking can increase risk. In the Nurses’ Health Study, women who drank about three to six alcoholic drinks per week were 15% more likely than women who never drank to be diagnosed with breast cancer. Women who drank the most (two or more drinks per day) were 51% more likely to be diagnosed with breast cancer than women who never drank.
Still, many people believe the heart benefits of drinking alcohol, especially red wine, outweigh any breast cancer risks. But it’s important to know that there are other ways to keep your heart healthy besides drinking alcohol. Women who are concerned about breast cancer risk may want to limit alcohol or avoid it completely.
The researchers reported that women who most closely stuck to the American Cancer Society guidelines for weight, diet, drinking alcohol, and exercise had a 22% lower risk of breast cancer compared to women who strayed the farthest from the guidelines.
Consider taking preventive medicine if you’re at high risk for breast cancer: In 2013, both the U.S. Preventive Services Task Force (USPSTF) and the American Society of Clinical Oncology (ASCO) released new guidelines on using hormonal therapy medicines to reduce risk in women with a high risk of breast cancer who haven’t been diagnosed.
The USPSTF guidelines say that doctors should offer the medicines tamoxifen and Evista (chemical name: raloxifene) to women aged 35 and older with a high risk of breast cancer who have never been diagnosed to reduce their risk. The task force didn’t recommend that women at average or low risk of breast cancer be offered these medicines.
In addition to tamoxifen and Evista, the ASCO guidelines also recommend that doctors talk to high-risk postmenopausal women about using the aromatase inhibitor Aromasin (chemical name: exemestane) to reduce risk.
In this study, the researchers estimated that between 2 million and 7.8 million women would benefit from taking hormonal therapy medicine preventively. In reality, only about 20,500 women between the ages of 35 and 79 were taking medicine to prevent breast cancer.
This low number may be due in part to side effects. Tamoxifen, Evista, and Aromasin all may cause side effects, some of them severe. Hot flashes and night sweats are side effects of all three medicines, though they’re more common with tamoxifen and Evista. Joint pain is a more common side effect of Aromasin. Aromasin also may weaken bones and make women more likely to break a bone. All three medicines can sometimes cause dangerous blood clots in rare cases. This complication is more common with tamoxifen and Evista.
While studies show the effectiveness of these medicines, other research has found that they’re not widely prescribed by doctors or taken by women at high risk of breast cancer because of concerns about side effects.
Talk to your daughters and other girls in your life about prevention strategies: Exercising, eating healthy food, maintaining a healthy weight, and avoiding alcohol all help reduce the risk of breast cancer. If these strategies start in girlhood, before the breasts begin to develop, breast cancer risk can be reduced even more than if these healthy behaviors start in adulthood.
Doing all that you can do to keep your breast cancer risk as low as it can be makes good sense. Exercising regularly, eating a healthy diet, maintaining a healthy weight, and avoiding alcohol are steps you can take to control several risk factors. You can learn much more about breast cancer risk and other steps you can to minimize your risk in the Breastcancer.org Lower Your Risk section.