Why dense breasts matter for breast cancer detection and prevention

Breast cancer awareness campaigns often focus on mammograms and self-exams. But there's another critical piece of the puzzle that has gotten far less attention until recently: breast density. A year after the FDA began requiring mammogram reports to tell women whether their breasts are dense, experts say it's important to explain what that means and why it matters. "About 40% of women are being diagnosed with dense breasts," Dr. Alpa Patel, senior vice president of population science at the American Cancer Society told ABC News. "You actually find out about your breast density from your first mammogram, and that will actually potentially change over time." Breast tissue is made up of fibrous tissue, which holds everything in place, glandular tissue, which produces and carries milk, and fat