A positive attitude may go a long way in reducing your chances of developing dementia, according to new research.
“This is one of the strongest studies on dementia and optimism I’ve ever seen,” says Dr. David Cappon, a psychologist and chair of neuropsychology at Tufts Medical Center. “This study helps answer the big ‘chicken and egg’ question. It suggests that a lack of optimism is not just an early symptom of dementia, but may actually be linked to risk in more meaningful and potentially upstream ways.”
Experts say the findings are particularly interesting because people can train themselves to be more optimistic. Here’s what the study found and why this link exists.
Significant optimism may protect your brain
For the study, researchers analyzed data from more than 9,000 participants in the Health and Retirement Study, a nationally representative sample of older Americans.
They collected information about participants’ general outlook on life using a common 10-item questionnaire used to measure optimism and pessimism. This was given at the beginning of the study and again two years later. The researchers also tracked who received a diagnosis of dementia during the 14-year follow-up.
Sade Stenlund, MD, lead author of the study and a research fellow at Harvard’s T.H. Chan School of Public Health, said her team evaluated participants based on how they compared to average levels of optimism.
The researchers crunched the numbers and found that a one standard deviation increase in optimism was associated with a 15 percent lower risk of developing dementia. “A one standard deviation increase is roughly equivalent to the difference between someone with average optimism and someone who is significantly more optimistic than average,” Dr. Stenlund says.
The researchers also conducted a sensitivity analysis (modeling that looks at different variables) and suggested that the association between optimism and lower dementia risk was strong and not due to other factors such as poor baseline mental health.
Although depressed mood can be an early symptom of dementia, the researchers found that the association between optimism and dementia remained consistent even when participants who developed dementia within the first two years were excluded from the study.
“These findings suggest the potential value of optimism in supporting healthy aging, which may be considered in future research on dementia prevention efforts,” the researchers concluded.
How attitudes shape dementia risk
Doctors say they are not shocked by the link. “In my experience, optimistic people cope better with their physical and mental health as they age,” says Dr. Kathryn Devons, chief of geriatrics at Northwells Phelps Hospital in Sleepy Hollow, New York.
There are several potential mechanisms behind this. “People who are more optimistic tend to engage in healthier behaviors, such as being more physically active, which is a known protective factor against dementia,” Stenlund says. “However, behavioral factors do not seem to explain much of this relationship.”
Another potential factor is that optimistic people are often better at managing stress, Dr. Devons says. “When you’re optimistic, you feel calm,” she explains. “This lowers blood pressure and reduces inflammation in the brain.” Being optimistic also lowers levels of the stress hormone cortisol in the brain. Elevated cortisol is another risk factor for memory loss, she says.
Dr. Clifford Segill, a neurologist at Providence St. John’s Health Center in Santa Monica, Calif., says being optimistic can also make your brain more active. Scientists have not yet discovered a clear “optimism pathway” in the brain, but higher brain functions are needed to stay optimistic, he says.
Finally, optimistic people are more likely to have strong social connections, which keeps their brains sharp, Stenlund says. “Biological pathways may play a role as well. For example, immune function is associated with both optimism and dementia, and may be one of the mechanisms underlying this association,” she says.
Optimism can be taught and is within reach.
Several doctors say optimism can be cultivated. “The reassuring thing is that optimism is not hardwired; it can be trained,” Dr. Capon says. “Randomized trials show that interventions focused on optimism can produce meaningful and lasting changes in biological markers, including those related to cardiovascular health.”
These interventions typically include strategies to mentally reframe the task and practice future-oriented thinking. That means imagining realistic, positive outcomes instead of being pessimistic about what will happen, Capon says. “On a day-to-day level, it can be something as simple as continuing a gratitude practice, pausing and resetting your perspective during stressful moments, or staying socially connected,” he says.
To practice gratitude, Stenlund recommends writing down three things you’re grateful for each day. She says this can help people develop a more positive outlook on the future.
Dr. Seguil also points out that adults should not underestimate exercise when it comes to preventing dementia. “Keeping your brain and body busy is good for brain health as you age,” he says.
