JJ Virgin explains that estrogen alone lowers breast cancer risk, while the increased risk from HRT comes from synthetic progestins, not bioidentical progesterone. The hormones themselves don't cause cancer; the formulation matters.
Turns out estrogen alone is actually associated with lower risk of getting and lower risk of dying of breast cancer. So we know it's more the progestogen component and specifically these synthetic progestins. And there are studies since then that suggest bioidentical forms of progesterone. So bioidentical means formulations or hormones that are similar to what our body produces. And there are studies that suggest bioidentical forms of progesterone are not associated with an increased risk of breast cancer. So I want to clarify that hormones do not cause breast cancer, and the increased risk that has been seen is largely associated with formulations that use synthetic progestins.
