1. Breast cancer only affects older women.

While it's true that the risk of breast cancer increases as you grow older, breast cancer can occur at any age. From birth to age 39, one woman in 231 will get breast cancer (<0.5% risk); from age 40-59, the risk is one in 25 (4% risk) and from age 60-79, the risk is one in 15 (nearly 7%). If a woman were to live to age 90, her risk of getting breast cancer over the course of her entire lifetime is one in 7, with an overall lifetime risk of 14.3%.

2. If you have a risk factor for breast cancer, you're likely to get the disease.

Getting breast cancer is never a certainty even if you have one of the stronger risk factors, like a breast cancer gene abnormality. Of women with a BRCA1 or BRCA2 inherited genetic abnormality, 40-80% will develop breast cancer over their lifetime and 20-60% won't. All other risk factors are associated with a much lower probability of being diagnosed with breast cancer.

3. If breast cancer doesn't run in your family, you won't get it.

Every woman has some risk of breast cancer, in fact increasing age is the biggest single risk factor for getting the disease. About 80% of women who get breast cancer have no known family history of the disease. If you do have a family history of breast cancer and are concerned, discuss it with your physician or a genetic counselor. You may be worrying needlessly.

4. Only your mother's family history of breast cancer can affect your risk.

A history of breast cancer in both your mother's and your father's family will influence your risk equally. That's because half of your genes come from your mother, half from your father. However, a man with a breast cancer gene abnormality is less likely to develop breast cancer than a woman with a similar gene. So, if you want to learn more about your father's family history, you have to look mainly at the women on your father's side.

5. Using antiperspirants causes breast cancer.

There is no evidence that the active ingredient in antiperspirants influences breast cancer risk. The supposed link between breast cancer and antiperspirants is based on misinformation about anatomy and a misunderstanding of breast cancer.

6. Birth control pills cause breast cancer.

Modern day birth control pills contain a low dose of the hormones estrogen and progesterone. Many research studies show no association between birth control pills and an increased risk of breast cancer. However, one study that combined the results of many different studies did show an association between birth control pills and a very small increase in risk. The study also showed that this slight increase in risk decreased over time. So after 10 years, birth control pills were not associated with an increase in risk. Birth control pills also have benefits, such as decreasing ovarian and endometrial cancer risk; relieving menstrual disorders, pelvic inflammatory disease, and ovarian cysts; and improving bone mineral density As with any medicine, you have to weigh the risks and benefits and decide what is best for you.

7. Eating high-fat foods causes breast cancer.

Thus far, studies have not been able to demonstrate a clear connection between eating high-fat foods and a higher risk of breast cancer, though the issue is still being investigated. Regardless, avoidance of high-fat foods is a healthy choice for a multitude of reasons: to lower "bad" cholesterol (low-density lipoproteins), increase "good" cholesterol (high-density lipoproteins), to make more room in your diet for healthier foods, and to help you control your weight. And excess body weight is a risk factor for breast cancer because the extra fat increases the production of estrogen outside the ovaries and adds to the overall level of estrogen in the body. If you are already overweight, or have a tendency to gain weight easily, avoiding high-fat foods is strongly advised.

8. A monthly breast self-exam is the best way to diagnose breast cancer.

Digital mammography or high quality film-screen mammography is the most reliable way to find breast cancer as early as possible, when it is most curable. By the time a breast cancer can be felt, it is usually larger than the average size of a cancer first found on mammography. However, breast examinations by you and your health care provider are still very important. About 25% of breast cancers are found only on breast examination (not on the mammogram), about 35% are found on mammography alone, and 40% are found by both physical exam and mammography. It makes good breast health sense to keep all your bases covered.

9. If I'm at high risk for breast cancer there's nothing I can do about it.

There are several effective ways to reduce the risk of breast cancer in women with high risk factors. Options include lifestyle changes, such as minimizing alcohol consumption, stopping smoking, and exercising regularly. Another option is medication (Tamoxifen, also called Nolvadex) and in cases of very high risk, prophylactic mastectomy surgery or prophylactic ovary removal may be offered. However, be sure that you consult with a physician or genetic counselor before you make assumptions about your level of risk. If you have any questions about this content, please let me know.