It's National Breast Cancer Awareness month, but how aware are you of breast cancer? Do you know how to separate fact from fiction? Can water from plastic bottles left in hot cars really cause breast cancer? How about underwire bras and antidepressants? The answers aren't always clear.
Here's the truth about these and other common beliefs, from two top breast specialists at New York University, Dr. Freya Schnabel and Dr. Deborah Axelrod...
MYTH: Underwire bras cause cancer
Some people think that by constricting breasts, underwire bras cause toxins to build up in breast tissue, leading to cancer. But they're wrong. "There is absolutely no truth linking the type of bra or breast pressure to cancer," says Dr. Axelrod. Adds Dr. Schnabel, "If underwire bras caused breast cancer, we would have seen a lot more breast cancer years ago, when women routinely wore tight corsets."
MYTH: Antiperspirants cause breast cancer
For years, "they" have been saying that antiperspirants expose the breasts to toxins that, over time, cause breast cancer. But there doesn't seem to be any scientific evidence for this belief. "This topic has been studied," says Dr. Schnabel. "There is no evidence linking antiperspirant use to breast cancer, so women who use these products can continue to do so."
MYTH: Water bottles cause breast cancer
Can women get breast cancer by drinking water from a plastic bottle that's been left in a hot car? Some people say yes, arguing that cancer-causing dioxin leaches into the water. But there is no dioxin in plastic water bottles, experts say. And researchers still haven't found a "smoking gun" implicating another potential carcinogen found in some plastics, bisphenol A. In any case, BPA-free plastics are now available to hold food and drinks.
MYTH: Mammograms cause breast cancer
Cancer can be caused by high doses of radiation, such as that delivered to survivors of atomic bomb blasts. But the dose of radiation from a modern mammogram is only 0.1 to 0.2 rad per picture - a tiny amount. How tiny? The amount of radiation delivered in a typical screening mammogram (in which four images are taken) is equal to the amount a woman receives simply by being exposed to the natural environment (background radiation) over a three-month period. "No studies have conclusively tied mammography radiation to an increased risk of breast cancer," says Dr. Schnabel.
MYTH: Lumpy breasts mean greater risk
Lumpy breasts don't seem to raise a woman's risk of breast cancer, though they can make it hard to find a cancer that has developed. And while four out of five breast lumps turn out not to be cancerous, it's always good to err on the side of caution and check with a doctor about any breast lump you notice. "Breast self-examination gets a bad rap," says Dr. Axelrod. "If you are familiar with what is normal for you, it may help avoid unnecessary biopsies."
MYTH: Breast cancer strikes only women with family history of disease
Although breast cancer runs in families, 80 percent of cases occur "sporadically" - that is, in women who have no family history. That's why it's important for women to have regular screenings, including periodic mammograms in women starting at age 40.
MYTH: Father's family history of breast cancer doesn't matter
A woman's father is just as likely as her mother to pass on a cancer-causing genetic mutation. That's because each individual gets half his/her genes from his father and half from his/her mother - so a woman can receive cancer-causing genes from her father. "If you inherit a genetic mutation linked to breast cancer from your father, it is just as likely to trigger the disease as one from your mother," says Dr. Schnabel.
MYTH: One in eight women gets breast cancer
American women have a one-in-eight chance of developing breast cancer, but that is over a lifetime (up to age 85). The risk is actually much lower in younger women: breast cancer strikes one in 233 women at age 30, one in 69 at age 40, one in 38 at age 50, and one in 27 at age 60.
What can be done to prevent cancer?
Have regular mammograms and clinical exams by a doctor for early detection. Get to know your breasts, and see your doctor for any suspicious changes. What else? Eat a healthy diet, do lots of physical activity, control your weight, avoid smoking, and limit alcohol intake.