Having higher density breast means that your breasts have more tissue than fat. Breast density is assessed with mammogram. Studies have consistently found that as breast density increases, so does the risk of breast cancer. Women with higher density are 4 to 6 times more likely to develop breast cancer than women with lower density breasts (breasts with a much greater proportion of fat than tissue). Here again, breast density is one of many small factors contributing to breast cancer risk. Having high density breasts is not something to fret about.