Back to articles

Breast density and your breast cancer risk

Breast Cancer Awareness, Show on Corporate Home

Perhaps your last mammogram report indicated that you have dense breast tissue, or maybe you got called back for a repeat mammogram because you have dense breasts. And now you’re wondering: How does the density of your breasts affect your health?

First, it’s important to understand what dense breast tissue is and what it isn’t. Contrary to what you might suspect, breast density isn’t related to the size or firmness of your breasts. Instead, it reflects the proportion of different types of tissue in your breasts— something only a mammogram can reveal.

Dense breasts have a lot of milk-producing and connective tissue and not much fatty tissue. Conversely, breasts that aren’t dense are either made up almost entirely of fatty tissue or a sizeable amount of it.

Dense breast tissue looks white on mammograms, as do tumors. As a result, dense breast tissue sometimes hides tumors. In contrast, fatty tissue looks almost black on mammograms, making white-colored tumors easier to detect.

Mammograms still a must

None of this means mammograms aren’t worthwhile if your breasts are dense. Most cancers show up on mammograms—even in women with dense breasts, the American Cancer Society reports. Still, the results of your mammogram may be less accurate or less clear than the results of a woman with more fatty breasts.

And while doctors don’t know why, dense breasts also raise your risk of breast cancer—although your overall risk may not be very high. That’s because many different things increase breast cancer risk, from a first pregnancy after age 30 to a family history of the disease. Your overall risk reflects all your risk factors considered together.

Most important: Talk to your healthcare provider about your risk factors and what screenings will be most beneficial for you. To learn more about cancer risk and prevention, find a provider near you.