All women are at risk for breast cancer, and as you get older, your risk increases. Researchers estimate that 1 in 8 women will be diagnosed with invasive breast cancer at some time in their lives. This means that the average woman has about a 12-13% risk of developing breast cancer. That might sound scary, but you can look at it another way: a 12-13% risk means there's an 87-88% chance that you WON'T develop breast cancer.
The National Cancer Institute (NCI) website has an interactive breast cancer risk assessment tool that can help you and your doctor figure out your individual risk of invasive breast cancer.
It's challenging to make sense of breast cancer risks. You probably want to know how much risk or how much protection is associated with each choice you make. Many risks are interrelated, which makes its hard to separate them out and measure each risk's singular effect. So it's hard to figure out the impact of each factor: the extra weight, the lack of exercise, and not eating fresh produce. That's why risk can be hard to understand.
On these pages, we're going to explain how risk is calculated and clarify the difference between absolute and relative risk.