Many studies have shown women with high bone density have an increased risk of breast cancer [98-102].

A meta-analysis that combined the results of 10 studies found women with high bone density had about a 60-80 percent higher risk of breast cancer compared to women with low bone density [102].

Why might high bone density increase breast cancer risk?

Having strong bones does not increase breast cancer risk.

Rather, high bone density is a marker for estrogen levels in the body (the more estrogen a woman produces in her lifetime, the more bone mass she has). These higher estrogen levels are linked to an increased breast cancer risk [19].

Learn more about estrogen and breast cancer risk.

Bone density and osteoporosis

Although women with high bone density have a higher risk of breast cancer compared to other women, they have a lower risk of osteoporosis [103].