Breasts that are too big and dense usually have fewer than fat and glandular tissue. Examination of the breast that mammograms often too thick to give less accurate results because it is more difficult to detect the abnormality. In his research, Vachon and his team followed the health history of 19,924 women over the age of 35 years who had never been diagnosed with breast cancer. The researchers looked at changes in size and diagnosis of breast cancer.

Then, 219 randomly selected women in a period of 6 years was diagnosed with breast cancer and 1900 cancer-free women. Women with cancer tend to have large breasts. Operation downsizing did not reduce breast cancer risk. Proven, 38.6 per cent which minimize breast cancer. Compare that with 37 percent of the group that did not make any changes.

Hormone replacement therapy in menopause can increase breast density also increase cancer risk by 20 percent. According to Dr. Joanne Mortimer, oncologists, the higher the estrogen, the greater the risk of breast cancer. "Breast density is closely linked with high levels of the hormone estrogen in the body," She said.