(CNN) - A new study shows caffeine could lead to changes in women's estrogen levels.
According to researchers, white women who drank more than two cups of coffee a day saw lower estrogen levels over time.
While Asian women who drank the same amount actually increased oxygen levels.
What that means for women's health--researchers don't know yet.
But in the long term, caffeine can change estrogen levels, which in turn can play a part in breast and ovarian cancers.
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