Dense breast tissue, mammograms, and what women should know

If your mammogram determines you have dense breast tissue, you may be at a higher risk of breast cancer and require additional imaging tests.

Key takeaways

• Breast density is a measurement of how much glandular and fibrous tissue you have in your breasts, compared to fatty tissue.
• Your mammogram results confirm if your breasts are dense or not dense.
• Dense breasts can increase your risk of breast cancer and make it harder to detect cancer with just a mammogram. Your doctor may recommend other tests, such as a breast MRI or ultrasound.

You may know that mammograms help find early signs of breast cancer. But did you know they also show if you have dense breasts? About half of ladies over age 40 in the United States have dense breast tissue.

Here, we discuss what breast density is and what it means for you and your breast health.

What is breast density?

Breast density is all about the types of tissue in your breasts. It has nothing to do with breast size or firmness.

Typically, breasts are made up of fibrous tissue (connective tissue), glandular tissue (the tissue that produces milk), and fat tissue. Your breasts are considered “dense” if you have more of the fibrous and glandular tissue and less of the fat tissue. This density can change over time, including during menopause.

When a radiologist, who reads mammograms and other imaging results, checks your mammogram, they look for possible signs of cancer, along with breast density. In 2024, the U.S. Food and Drug Administration (FDA) started requiring that all mammogram reports include whether your breasts are dense or not.

Why does breast density matter?

If your mammogram report says you have dense breasts, it can mean you’re at a higher risk of breast cancer. Dense breast tissue is also harder to see on a mammogram.

Fatty tissue on a mammogram looks darker. But dense tissue looks white—the same color as a breast mass or tumor. For this reason, if you have dense breasts, your doctor may recommend follow-up imaging tests, in addition to your regular mammogram, to check for breast cancer.

What screenings should I get if I have dense breasts?

Even with dense breasts, self-breast exams and regular mammograms are still important. Often, a 3D mammogram can see more of your tissue than a 2D mammogram, so doctors typically recommend it for women with dense breasts. Depending on your doctor and breast cancer risk, you may also benefit from other tests, such as:

• Magnetic resonance imaging (MRI): 3T MRI is the fastest diagnostic MRI technology available. It provides high-quality, detailed images of the breast to detect any signs of cancer.
• Breast ultrasound: This test takes pictures of small areas inside the breast using high-frequency sound waves from a handheld device (transducer). Images can show cysts, tumors, and cancer that may not appear on a mammogram.

It’s important to remember that not all tests are helpful for every person. Sometimes, MRIs and ultrasounds show false positives, meaning tissue that looks like cancer but isn’t. Also, your insurance might not cover additional testing beyond mammograms.

The best approach is to talk with your women’s health team. Together, you can determine which imaging tests are most beneficial for your specific situation.

Questions to ask at your next mammogram

Staying informed is super important when it comes to breast health. At your next mammogram, make sure you can answer these questions. And if you can’t, ask your team:

• Do I have dense breasts, based on my mammogram? If yes, what does that mean for me?
• What is my personal risk for breast cancer?
• Should I get other screenings? What are the benefits and drawbacks of each additional test?
• How often do I need a breast screening?

Schedule your mammogram today

At LCMC Health, our women’s health team works hard to make sure all women in and near New Orleans have access to essential services—including preventive screenings, such as mammograms. We’re here to help you take control of your health and achieve a healthier future.

Learn more about breast health and schedule a mammogram today.

Related questions about breast health

How do I know if my breasts are dense?

A mammogram is the only way to know if your breasts are dense. You or your doctor cannot physically feel dense breasts during a breast exam.

What are breast density categories?

Breast density has four categories:

1. Almost all fatty breast tissue.
2. Mostly fatty tissue with some areas of dense glandular and fibrous tissue.
3. Many areas of dense glandular and fibrous tissue, with some areas of fatty tissue.
4. Almost all dense glandular and fibrous tissue.

What causes dense breast tissue?

Most people inherit their breast density from an immediate relative. But other factors are associated with dense breasts, including hormone therapy and low body mass index (BMI). Breast density tends to decrease with age and after having children.

A little something extra, delivered to your inbox.

We're making health a reason to celebrate!

Fill out the form below to receive our monthly wellness email to keep you informed about healthcare trends, information about our providers and services, and of course, tons of delicious recipes (that are good for you!) from our expert dietitians.

Sign-Up