5 Breast Cancer Myths You Hear All the Time That Just Aren’t True

Updated: Oct. 10, 2022

We don't know everything about breast cancer, but we do know these commonly held beliefs are actually myths.

Doctors don’t always know what causes breast cancer, but decades of research have led to an increased understanding of the risk factors and the disease in general. One example of this is the mammogram. “We know that women who undergo screening mammography have an improvement in breast cancer survival,” says Trevan D. Fischer, MD, surgical oncologist and assistant professor of surgical oncology at John Wayne Cancer Institute at Providence Saint John’s Health Center in Santa Monica, California. “Another example is research that has characterized the different subtypes of breast cancer and developed different treatments for each subtype.”

While there is still much more to be learned about breast cancer, here are some common breast cancer myths that you can luckily put to rest:

Myth: Having larger breasts puts you at greater risk

Truth: “The majority of the tissue that comprises the breast is fatty tissue and not the ducts and lobules,” says Dr. Fischer. “The ducts and lobules are where the vast majority of breast cancer arises, therefore have more fatty tissue in the breast does not increase your risk.” One physical characteristic of your breast that may increase your risk, however, is breast density. Another is obesity, which is linked to a long list of cancers, including breast cancer, in women past menopause.

Myth: If breast cancer doesn’t run in your family, you’re probably safe

Truth: While you do face a greater risk of getting breast cancer if it runs in your family, especially if your sister or mom had it, Richard Reitherman, MD, PhD, medical director of breast imaging at MemorialCare Breast Center at Orange Coast Medical Center in Fountain Valley, California, notes that approximately 85 percent of women who are diagnosed have no family history of the disease.

Myth: Taking birth control pills increases your chances of developing breast cancer

Truth: “There are no definitive studies that have linked birth control pills to breast cancer,” says Janie Grumley, MD, breast surgical oncologist and Director of the Margie Petersen Breast Center at Providence Saint John’s Center and associate professor of Surgery at John Wayne Cancer Institute in Santa Monica, California. “In fact, there are studies that suggest they may be protective while other studies suggest slightly increased risk.”

Research continues on the potential relationship between the pill and the disease, however, enough recent studies have shown no measurable connection that doctors presently do not consider birth control to be a breast cancer risk factor in most women.

Myth: Using deodorant can lead to breast cancer

Truth: The lymph nodes, where some breast cancers can spread, are located beneath the underarm, a fact that has inspired several rumors about a link between underarm products and the disease.

“We don’t recommend deodorant prior to mammograms as some metallic artifacts may be seen on a mammogram but no definitive link has be made to breast cancer,” says Dr. Grumley.

Myth: Breast cancer is an older woman’s disease

Truth: The fact that most cases of breast cancer occur in women over 50 often overshadows the reality that a full 25 percent of breast cancer patients are younger than 50. Doctors recommend women begin performing monthly breast self-exams when they turn 20, along with a clinical exam every three years. Most women should begin getting annual mammograms at 40, but if breast cancer runs in your family, your doctor may suggest scheduling your first at 35 or even 30.