Closeup of the chest of a woman wearing a bra, and of a woman not wearing a bra, with an inset showing the mammograms of breasts that are fatty and dense.

Breast Density

The mammograms in this post show the differences in how fatty and dense breasts look on a mammogram, and the challenge of spotting breast cancer in dense breasts (click on “continue reading” to see the full post and the mammograms). This post accompanies our podcast on breasts and nipples.

Mammograms of four different types of dense breasts.
Mammograms showing how easy it is to detect cancer in a fatty breast as opposed to a dense breast.
Four different breasts, with the question of "can you spot the tumors on these mammograms?"

Three excellent websites for women about dense breasts:

CDC Basic Info About Dense Breasts The website of the CDC.

Dense Breast Info by Dr. Wendy Berg and JoAnn Pushkin A leading website about dense breasts. The Story of A Woman whose Breast Cancer was missed on her mammograms over multiple years and on several consecutive screening mammograms.