Health & Wellness

Keep Your Brain Sharp

Science has shown that there are things you can do every day to make sure your brain stays in shape

  

By Wendy Haaf

Photo: iStock/eggeeggjiew.

Wouldn’t it be wonderful if you could take a pill that would help you stay as mentally sharp as possible with the passing years? While such a medication doesn’t exist, there are healthy habits that do seem to reduce your risk for cognitive decline and dementia, and better yet, they also protect your overall health and well-being and are enjoyable to boot. So what can you do to keep your brain in top form?

Work Up a Sweat

“There’s pretty good evidence that exercise helps maintain good cognitive function as we age and mitigates dementia risk,” says Teresa Liu-Ambrose, a professor of physical therapy and a Canada Research Chair in Physical Activity at the University of British Columbia’s Djavad Mowafaghian Centre for Brain Health in Vancouver.

In one landmark human study, sedentary healthy older adults who participated in a moderate exercise program saw gains in the volume of the hippocampus (a brain structure associated with memory that typically shrinks with age), as well as improvements in how the brain functions to complete a task.

Another trial found that when people aged 60 to 80 stuck to a graduated walking program (starting with 15 minutes and working up to 45 minutes to an hour, three days a week) for one year, the number of their brain cells and complexity of connections among them had grown to resemble those of 20–30-year-old brains. (These connections, which generally weaken with age, are linked with better performance on a number of cognitive tests.) Aerobic exercise also seems to boost the release of substances that act as Miracle-Gro for brain cells, causing the cells to sprout more new branches and even fostering the genesis of new cells.

A growing body of research suggests that resistance exercise, such as twice-weekly weight training, is also good for your grey matter. “We’ve shown that weight training can change how the brain functions, so that it can work better under challenging conditions,” notes Liu-Ambrose. What’s more, she and her colleagues have demonstrated that this type of exercise stalls further damage to white matter (part of the fatty insulating material that sheathes brain cells) in people who already have small lesions in this area. “Evidence suggests that exercise can in fact be potent enough that it could at least slow down these pre-existing conditions,” Liu-Ambrose says.

Control Cardiovascular Risk

According to a 2015 report from the World Dementia Council, managing cardiovascular risk factors, including high blood pressure, diabetes, smoking, and obesity, is, second only to exercise, “associated with reduced risk for cognitive decline and may even reduce the risk for dementia.” Smoking, for instance, increases the risk for dementia by 45 per cent, according to the Alzheimer Society of Canada.

“All of these factors affect circulation to the brain, and by stopping smoking and having good control of blood sugar and blood pressure, you optimize the function of the brain the same way you optimize heart function,” explains Dr. Tarekj Rajji, chief of geriatric psychiatry at Toronto’s Centre for Addiction and Mental Health and a scientist with the Campbell Family Mental Health Research Institute. By promoting healthy functioning of the heart and blood vessels, controlling these risk factors reduces the risk for the second leading cause of dementia—vascular dementia, caused by reduced blood flow to the brain due to stroke, mini-stroke, or damage to small blood vessels.

Maintaining a healthy body weight also seems to mitigate dementia risk.

“Being overweight triggers an inflammatory process in the body that probably has effects on the brain,” notes Heather Keller, a registered dietitian, Schlegel Research Chair in Nutrition & Aging at the Schlegel-UW Research Institute for Aging, and professor of kinesiology at the University of Waterloo.

Challenge Your Mind

There’s a good deal of evidence that the more you challenge your brain and the more varied and complex the activities you engage in to do so, the better your cognitive health as you age and the lower your risk for dementia. From taking dance and language classes to attending art exhibitions, reading, doing crossword puzzles, and learning new skills such as photography and quilting, engaging in cognitively stimulating activities is linked with a lower risk for both cognitive decline and dementia.

For example, in one study that tracked more than 7,000 older adults for up to seven years, the risk of developing dementia was 38 per cent lower among those with the highest levels of leisure and social activity. (Leisure activity included pursuits such as reading, playing cards, and attending classes, while social activity included visiting with friends.) Doing mentally demanding activities and, particularly, learning new things forges new connections between brain cells, and the richer and more complex the patterns of connection in the brain, the thinking goes, the longer we’ll be able to compensate for any damage due to aging or diseases such as Alzheimer’s.

Dr. Rajji is currently studying whether a cognitive exercise program combined with magnetic stimulation of the brain can prevent cognitive decline and dementia in one specific high-risk group: those with a history of depression. (For more information on the study, go to camh.ca and search for “PACt-MD.”)

Forge Strong Social Connections

Study after study has linked strong, supportive relationships with friends and family members to a lower likelihood of both cognitive decline and dementia. And while it’s possible that people in the early stages of the latter begin to withdraw socially, recent research suggests that social activity—including volunteering and attending club or religious ceremonies—really does protect the brain, even in very late life.

In one study published in 2011, for example, scientists were able not only to look at changes in cognition and social functioning but also to see which came first. They followed 1,138 adults (average age: 79.6) with no signs of dementia for an average of five years and found that cognitive test scores dropped 70 per cent less among the most socially active seniors than among those with the least crowded social calendars.

Volunteering, in particular, may boost brain power. “There’s emerging evidence that volunteering is associated with cognitive gains [in older adults],” says Nicole Anderson, a senior scientist with the Rotman Research Institute at Baycrest Health Sciences in Toronto.

Eat a Plant-Forward Diet

“While we’re learning more all the time, a key thing that’s well-founded in the research is that a plant-based diet seems to be important [to brain health],” Keller says. That means an eating pattern that emphasizes fruits, vegetables, whole grains, beans, legumes, nuts, healthy oils, and low-fat dairy products and includes only scant amounts of red meat, sweets, and highly processed and fried foods (as in the Mediterranean, DASH, and MIND diets).

“The Mediterranean diet has shown some pretty convincing evidence as being able to reduce the risk of developing Alzheimer’s disease, for example,” says Rachel Murphy, an assistant professor and researcher with the Centre of Excellence in Cancer Prevention at the University of British Columbia’s School of Population and Public Health in Vancouver.

In one study, older people whose eating patterns most closely followed the MIND diet (which combines the Mediterranean and DASH diets and focuses on preserving brain health) were 53 per cent less likely to develop Alzheimer’s over a five-year period than were seniors with more typical North American eating habits; even moderate adherence to the MIND principles was linked with a 35 per cent reduction in Alzheimer’s risk. (You can download the Brain Health Food Guide, which is based on the MIND diet, at baycrest.org.)

In addition, “there’s some pretty good evidence that the long-chain omega-3 fatty acids in fatty fish might slow cognitive decline in people who are otherwise healthy,” Murphy says. Consuming fish itself, rather than fish oil capsules, provides the strongest evidence of this.

And since our ability to absorb vitamin B12 drops with age and a deficiency can cause symptoms that mimic dementia (as well as nerve damage that may be irreversible if not caught early enough), ask your doctor whether you should consider adding fortified foods or a supplement to your diet. “You can do a pretty easy blood test for B12,” Murphy says.

Don’t Ignore Hearing Loss

“There is a well-established link between hearing loss and the chance for cognitive decline,” notes Marilyn Reed, the audiology practice advisor at Baycrest Health Sciences in Toronto.

While it’s not yet clear if there’s a cause and effect relationship between the two or if the conditions share a common underlying disease process, we know that hearing loss increases the odds for social isolation and depression, both of which are powerful risk factors for dementia.

Most of the time, hearing problems go unaddressed: only about one person in five who could benefit from hearing aids actually uses them. Reed is involved in a pilot project aimed at finding out whether screening low-income seniors for hearing loss and providing education on communication strategies and relatively inexpensive, non-prescription amplifying devices might mitigate these risk factors.

“If we can help people to communicate better and participate more socially, we’re hoping we can have a beneficial impact on their well-being, in terms of their mental and cognitive health,” she says.