Exercising your body and mind can help stave off memory problems as you age, and some of these benefits may be even greater for women, a new study suggests.
The study looked at cognitive reserve, or the brain's ability to withstand the effects of diseases like Alzheimer's without showing a decline in thinking or memory skills.
Women, but not men, had greater cognitive reserves if they exercised regularly and took classes, read or played games. Taking part in more mental activities improved thinking speed for both women and men.
"Begin building that cognitive reserve now, so the money is in the bank for down the road if our brains need it," said study author Judy Pa. She is the co-director of the Alzheimer's Disease Cooperative Study and a professor of neurosciences at the University of California, San Diego.
"It is never too early or too late to engage in physically and mentally stimulating activities, and it is a good idea to try new activities to continue challenging the brain, mind and body to learn and adapt," Pa said.
The study included 758 people (average age, 76). Some participants showed no evidence of thinking or memory problems, others had mild cognitive impairment, and some had full-blown dementia when the study began.
The participants underwent brain scans and took thinking speed and memory tests. The researchers compared scores on these tests to brain changes associated with dementia to calculate a cognitive reserve score.
Women who reported more physical activity had a greater thinking speed reserve, but this wasn't seen in men. Greater physical activity wasn't linked to improved memory reserve in men or women. Women who read, took classes and played cards or games more frequently also showed a greater memory reserve.
The study wasn't designed to say how, or even if, these activities improved brain function, just that there is a connection.
Exactly why women seemed to accrue more benefits from these activities than men isn't fully understood yet, Pa said.
"There is still more work to be done in this area to better understand the differences observed in women and men, which could be related to the types of physical and mental activities undertaken by each sex/gender group," she said. For example, women reported more group-based classes than men.
The researchers also looked at how the APOE4 gene, which increases the risk for Alzheimer's disease, affected the results and found this gene dampened the added benefits of physical and mental activities on cognitive reserve in women.
The study did have some limitations. People were asked to report their own physical and mental activity and may not have recalled them accurately.
The research was published online July 20 in the journal Neurology.
It is too early to draw any firm conclusions on how mental and physical activities affect brain health in men or women, according to experts who were not involved with the study.
"It appears that the impact of self-reported physical and cognitive activities on cognitive reserve was more pronounced in women," said Dr. Howard Fillit. He is the co-founder and chief science officer of the Alzheimer's Drug Discovery Foundation in New York City. "These are just associations, and more research is needed to confirm the findings."
What's more, the researchers didn't control for factors that could have affected the results, including participant's education levels, Fillit said.
There are things to do to protect and foster your cognitive reserve now, he said. "Exercise regularly, eat a healthy Mediterranean-style diet, get good sleep, avoid stress, alcohol and smoking, and manage your diabetes and high blood pressure," Fillet advised. "The age of prevention is upon us, and we can delay the onset of cognitive decline and Alzheimer's or slow it down with these prevention methods."
There is also a role for testing for the APOE4 gene in some people, he noted.
Such tests are readily available. "It's the job of the physician to inform, educate and determine the patient's attitude toward knowing their risk factors for Alzheimer's disease, including genetic risk factors," Fillet said.
Not all APOE4 carriers will develop Alzheimer's, he pointed out. "Prevention measures may be even more important in people who have this gene," Fillet added.
Dr. Thomas Vidic is a clinical professor of neurology at Indiana University and a fellow of the American Academy of Neurology. "This paper suggests that the effects of physical and mental activity for preventing cognitive decline or functioning better with Alzheimer's is stronger in women than men," but this doesn't mean men shouldn't participate in these enriching activities, he said.
"We are still learning how to measure cognitive reserve and don't know how much is significant or how much we need to get to the next level," Vidic said. It's possible that different measures of cognitive reserve may better reflect the benefits of these activities in men, he added.