A gene called apolipoprotein E (ApoE) is one of the main genetic risk factors for Alzheimer’s disease. Not everyone with that gene, however, develops Alzheimer’s or any other form of dementia.

Numerous studies have been done to try to determine why some people with ApoE have Alzheimer’s and others escape the condition. While there is no definitive explanation, a recent study suggests that one possible reason lies in how people perceive getting older.

A study published in PLOS One found that among people with the ApoE gene, those who view aging with a positive and optimistic outlook have a lower risk of developing dementia than those with negative beliefs about getting older.

Over four years, researchers questioned more than 4,700 people without dementia over the age of 60 about their attitudes toward aging. Participants filled out questionnaires which included statements such as “The older I get, the more useless I feel,” to which participants could agree or disagree. Results showed that those who had positive attitudes about aging were nearly 50% less likely to develop dementia.

One explanation for this finding is that the stress that comes with negativity can cause actual harm to the brain. Positivity may help protect the brain by reducing the amount of stress-related chemicals in the brain.

Fortunately, boosting your outlook is a modifiable risk factor. Focusing on what you can do as you get older and learning more about the opportunities for older adults in your community may help. Feelings of uselessness or hopelessness can be signs of depression.

If you experience these thoughts and feelings, consult your doctor.

This article originally appeared in Mind, Mood & Memory, a publication of the Department of Psychiatry at Massachusetts General Hospital, dedicated to maintaining mental fitness for middle age and beyond.

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