Why Are Women More Likely to Develop Alzheimer's Disease as They Age?

senior woman portrait outdoors
senior woman portrait outdoors

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Alzheimer's disease is a progressive condition that causes memory loss and impacts cognitive functions. Out of the six million-plus people who develop this disease, two-thirds are women, though (almost twice more than men). Why is that exactly? Harvard University researchers explain that the lifespan of women is longer. For example, female babies born in 2019 are predicted to live five years longer (81 years) than male babies (76 years). And Alzheimer's disease typically comes about based on age: Four out of 1,000 people between 65 to 74 years of age develop Alzheimer's disease each year, 32 out of 1,000 people between 75 to 84 develop the disease each year, and 76 out of 1,000 who are 85 and older develop the disease each year.

In part, females are more likely to experience Alzheimer's disease than males based on the fact that they live longer. However, Harvard researchers have also studied amyloid, a piece of Alzheimer's disease pathology. They believe that this could be deposited to ward off brain infections. In turn, the development of Alzheimer's disease could be the result of the brain's immune system.

Related: Eating Antioxidant-Rich Foods Can Help Ward Off Alzheimer's Disease

Another reason women tend to have the disease more than men is because of the higher likelihood of experiencing an autoimmune disease. Females have them twice as often. The researchers explain that women often have stronger immune systems than men, plus, several autoimmune diseases come about during pregnancy. While they note that more research will help their analysis, they share that women's immune systems may become stronger when protecting a fetus from infections. As their immune systems get stronger, they develop a larger amount of amyloid plaques than in men.

When putting all of their insights together, the Harvard research team explains that in addition to age, the reason women experience Alzheimer's more often is based on them having more amyloid plaques. Women and men can still reduce Alzheimer's risks by staying physically fit through aerobic exercise (think: walking and biking) for about 30 minutes, five days a week, eating healthy fats, like fish and avocados, getting plenty of rest each night, and communicating socially to keep cognitive functions in their best condition.