Estrogen Staves Off Dementia

Women under 50 who've had their ovaries removed double their risk of disorders like dementia and Parkinson's disease later in life if they don't undergo estrogen-replacement therapy, new research reveals. The findings may lead to more aggressive treatment for premenopausal women who don't produce estrogen naturally, Time reports.

Researchers found a "critical age window" in which the hormone is helpful, but between 50 and 65 "it's still unclear," said the lead researcher. The study, performed in two stages, looked at women with both ovaries, one ovary, and no ovaries; the results showed a clear connection between cognitive function and estrogen, whether supplied naturally or through hormone therapy. (More health stories.)