Why do More Women than Men get Alzheimer’s?

It’s not fair, but it is true: Twice as many women as men get Alzheimer’s. No one is sure why, but there are some dots in research that could well be connected, according to Lisa Mosconi, the associate director of the Alzheimer’s Prevention Clinic at Weill Cornell Medical College.

Gender—even when differences in lifespan between men and women is taken into account—is one of those dots. Another dot is that removing the ovaries or the uterus, increases the risk of dementia in women. The third dot is that women possibly start getting the disease earlier than men, according to Mosconi’s research. “It looks like the disease starts when your brain is the most discombobulated it’s ever been past puberty,” she says. “[W]omen have more years to experience the disease not because they live longer, but because they start earlier.”

Furthermore, while estrogen production plunges in women during menopause, during “male menopause” (androgen) testosterone levels decline more slowly and gradually, just one percent each year.

Estrogen may be the key. As Mosconi wrote in an editorial in the New York Times, “The latest research indicates that estrogen serves to protect the female brain from aging. It stimulates neural activity and may help prevent the buildup of plaques that are connected to the onset of Alzheimer’s disease. When estrogen levels decline, the female brain becomes much more vulnerable.”

Many factors affect your risk for Alzheimer’s, including genetics and lifestyle, and more research needs to be done before anyone can say definitively whether estrogen replacement therapy is the answer to preventing Alzheimer’s.

In the meantime, do what you can to protect your cognition: exercise regularly, eat lots of fruits, vegetables, and salmon (which is high in omega-3-fatty acids), and stay mentally active.