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.
A paper strongly suggests that breast cancer prevention should start early in life because nearly 25% of breast cancers are diagnosed in women younger than age 50 in developed countries.
The paper was published online on July 22, 2015 by the journal npj Breast Cancer. Read “Preventing breast cancer now by acting on what we already know.”
The lead author of the paper is Graham Colditz, M.D., an internationally known epidemiologist and public health expert who is a member of the Breastcancer.org Professional Advisory Board. He is the director of Prevention and Control at the Siteman Cancer Center at the Washington University School of Medicine in St. Louis, MO.
In the paper, Dr. Colditz and his colleague Kari Bohlke describe the factors that most commonly influence breast cancer risk:
- increased exposure to the hormones estrogen and progesterone
- changes in women’s height growth rate and reproductive patterns
- lifestyle changes, including diet, that come about because of economic development
The researchers also quote breast cancer prevention task force reports urging people to focus on risk factors during specific time periods in a woman’s life:
- in childhood, before and during breast development
- in young adulthood/adulthood before the breasts fully mature with the birth of a woman’s first child
Research has shown that girls who eat a high-calorie, low-nutrient diet that contains few vegetables and fruits and get little or no exercise/physical activity are more likely to start having their periods earlier. This means that the body starts producing more estrogen -- so girls who start menstruating earlier are exposed to more estrogen over their lifetimes. We know that estrogen can make breast cancer develop and grow. Girls who eat more vegetables and whole grains are more likely to start their periods later, which means they’re exposed to relatively less estrogen over their lifetimes.
“Timing of prevention therefore matters,” the researchers wrote. “Because 22% of breast cancer is diagnosed in premenopausal women and is often more aggressive than cancers diagnosed in postmenopausal women, it makes sense to start prevention early in life when it can have maximum impact. For example, prevention begun in childhood and continuing through adolescence and early adult years can reduce development of premalignant or intermediate lesions that are on the pathway to breast cancer.”
They recommend the following strategies to reduce breast cancer risk and have calculated how much of a difference each would make in the number of cases diagnosed in the United States:
- Eat a diet full of vegetables, fruits, and whole grains in childhood and continue eating that way throughout life: would prevent 3% of breast cancers
- Be physically active as a child and continue exercising throughout life: would prevent 11% of breast cancers
- Avoid gaining weight as you age: would prevent 25-32% of breast cancers
- If you do gain weight as you age, lose about 10% of your body weight (and keep it off) after menopause: would prevent 25% of breast cancers
- Limit or avoid alcohol between your first period and the birth of your first child: would prevent 3% of breast cancers
- Limit or avoid alcohol throughout life: would prevent 3% of breast cancers
- Avoid using medicines such hormone replacement therapy that contains estrogen and progesterone: would prevent 3% of breast cancers
- Women at high-risk for breast cancer because of family history or an abnormal gene should consider taking preventive medicine such as tamoxifen or Evista (chemical name: raloxifene): would prevent 11% of breast cancers
Dr. Colditz urges communities, policy makers, schools, and parents to talk to girls 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.
“If we act and act now, shifting the balance and focus to earlier life, supported by additional resources devoted to implementing prevention, bringing messages and bolstering lifestyle and risk-reduction behaviors during the critical time points in life, we stand a good chance of significantly reducing the burden of breast cancer now and for future generations,” he wrote.
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 take to minimize your risk in the Breastcancer.org Lower Your Risk section.