Breast Density Matters

Dense breasts have two risk factors: they increase your risk for breast cancer and dense breasts make it difficult for breast cancer to be seen on a mammogram. There are steps you can take to minimize your risk. Know and understand your breast density.

There are 4 categories of breast density.

Category C and D are considered “dense breasts.” Dense breasts are common and normal. In fact, about 43% of women ages 40+ have dense breasts.


The denser the breast, the higher the risk of getting breast cancer.

Having dense breasts is a more prevalent risk factor than having a family history of breast cancer.

Mammograms miss about 40% of breast cancers in the densest breasts.

Dense breasts make it harder to see cancer.

Dense breasts make it harder for radiologists to spot cancer. On a mammogram, dense breast tissue shows up as white and so does a cancerous tumour. This creates a camouflage effect.

Mammograms are a highly effective tool for women with fatty breasts, but mammograms alone are not enough for women with dense breast tissue. If you have dense breasts, you may want to discuss additional screening, such as ultrasound or MRI with your healthcare provider.

How to Find Out Your Breast Density 

It's your health. Be breast informed.

Easily learn about your province/ territory's screening program practices, the latest research by breast cancer experts and how to advocate for the screening you need.

Accurate, current and relevant information can help you have informed conversations with your health care provider and make the best decisions for your health. Select your province/territory.

Learn about breast screening practices in your province or territory.

Stay informed. Read our guides and reports.