You can do a great deal to keep your brain healthy by addressing the risk factors that contribute to the development of dementia
By Wendy Haaf
Amid headlines warning of a projected increase in dementia cases in Canada and heralding new drugs to treat Alzheimer’s disease, a few important facts sometimes get overlooked.
First, we already have tools that can dramatically reduce the likelihood of developing dementia and even improve brain function, and the benefits of these strategies far outweigh the potential effects of even the most cutting-edge treatments. Some of these preventive strategies have been successfully employed for the past two decades.
“There are actually fewer people living with dementia today than we would have expected 20 years ago,” says Dr. Samir Sinha, director of Health Policy Research at the National Institute on Ageing (NIA) at Toronto Metropolitan University and a geriatrician at the Sinai Health System and the University Health Network in Toronto.
In fact, “the incidence has decreased by about 25 per cent over the past 20 years, mostly due to smoking cessation and better management of hypertension, and, to some extent, improvements in education and living standards in high- and some mid-income countries,” explains Dr. Howard Bergman, professor of Family Medicine (Geriatrics) and Oncology in the Faculty of Medicine and Health Sciences at McGill University in Montreal. If scientists were to discover a medication that could accomplish something similar, or even exert half as much of an effect, “people would be jumping up and down,” he adds.
Yet that’s only a fraction of what we could achieve by further improving just one of those variables. According to World Health Organization figures, “the number of adults between 30 and 80 in Canada with untreated hypertension is about 30 per cent, and the number with hypertension that is not well controlled is 39 per cent,” Bergman says. He adds that the figures for diabetes and high levels of unhealthy cholesterol—both risk factors for dementia— are probably similar.
This is one of the reasons that proactive brain-health promotion and prevention strategies form one of the cornerstones of the new Quebec Alzheimer Policy, which Bergman co-authored with his colleague, Dr. Isabelle Vedel, an associate professor in McGill’s Department of Family Medicine. “This approach is not only realistic but also proven effective,” Bergman says.
If you’re wondering what difference addressing risk factors could make for someone in their 60s or 70s, Bergman points to a study that has shown “that if you treat older people with hypertension, you can reduce their dementia risk so that it’s the same as that of older people without hypertension.”
This means that you should get your blood pressure checked regularly, and if it’s elevated, work with your primary-care provider to bring it down. The same goes for your blood sugar and LDL-cholesterol levels. “It’s very important that people understand the importance of detecting and being treated for these things if they want to take care of their brain,” Bergman says.
The Risk Factors
“The challenge is that in society as a whole, there’s a natural assumption that dementia is almost a normal part of aging,” Sinha says. “That contributes to this feeling of inevitability.” While as a specialist in aging he sees the impact of dementia in his day-to-day practice, “it’s heartening to know that a growing body of research is demonstrating that there are at least 14 practical things most of us can do that can prevent or delay our risk for developing dementia,” he says. (This knowledge is the basis of the NIA’s new Small Steps, Big Difference campaign.)
According to a 2024 report from the Lancet Commission on dementia prevention, intervention, and care, the following potentially modifiable risk factors account for an estimated 45 per cent of dementia cases worldwide: less education, high blood pressure, high cholesterol, physical inactivity, excessive alcohol consumption, smoking, traumatic brain injury, diabetes, obesity, hearing loss, vision loss, depression, social isolation, and exposure to air pollution. High cholesterol and vision loss were added to this list in 2024, following up the commission’s 2020 report, which estimated that 40 per cent of dementia cases worldwide were related to the other 12 risk factors.
Two separate studies published in 2024 suggest that that number could be even higher here in Canada. Drawing on data on approximately 30,000 people enrolled in the Canadian Longitudinal Study on Aging, researchers at the Lawson Research Institute and St. Joseph’s Health Care London (Ont.) estimated that 49.2 per cent of dementia cases in Canada could potentially be prevented by addressing just 12 risk factors. (Their list differed slightly from that of the Lancet Commission, substituting sleep disturbance for air-pollution exposure.)
The four factors with the greatest influence are physical inactivity (10 per cent of cases), hearing loss (6.5 per cent), and hypertension (6.0 per cent). A whopping 83 per cent of study participants did not meet the recommended guidelines of 150 minutes per week of moderate-to vigorous-intensity physical activity.
And accumulating evidence from studies in which participants are provided with guidance and support to improve these issues indicates that these strategies can indeed protect and even improve cognitive function.
In 2025, researchers presented results of one such trial at the Alzheimer’s Association International Conference in Toronto. Called the US POINTER study, it followed 2,000 older adults who were considered at risk for developing cognitive impairment (due to factors such as sedentary lifestyle and borderline high blood pressure, blood sugar, and cholesterol) over two years. Participants were randomized into two groups, both of which were focused on improving four domains: exercise, nutrition, social and intellectual engagement, and heart health.
“One arm was self-guided—people were told what they needed to do,” explains Howard Chertkow, scientific director at Baycrest’s Kimel Family Centre for Brain Health and Wellness in Toronto. “The other arm received a more structured intervention,” which included a defined activity program with measurable goals and far more peer meetings. Goals were modest at first—just 10 minutes of exercise at a time, for instance—and gradually grew. “Both arms benefited in terms of reducing their risk,” Chertkow says.
In addition, “both groups saw improvements in cognition from baseline to two years,” study co-author Laura Baker, professor of Gerontology and Geriatrics at the Wake Forest University School of Medicine in Winston Salem, N.C., explained during an October 2025 public webinar. However, the more intensive group saw greater gains. “The extra benefit for the structured group was as if we had slowed the cognitive aging clock by one to two years,” she said. In other words, participants in that group “performed on tests as if they were one to two years younger.”
Encouraging Results
Early results from a study underway at the Kimel Centre are similarly encouraging. (This study is part of a larger Canadian equivalent to the US POINTER study, called CAN-THUMBS UP.) In the Kimel Centre trial, participants “get an assessment and see what their risk factors are, and then they’re given education and access to programs,” Chertkow explains.
For example, “if they need more exercise, we have a gym with group classes.” The study targets risk factors in five lifestyle domains: physical activity, mental well-being, brain-healthy eating, cognitive engagement, and social connections.
Nicole Anderson, associate scientific director at the Kimel Centre and one of the study’s lead investigators, recently presented preliminary results on 258 people who had been followed for at least six months. “They were an average age of 69 but ranged from 50 to 95,” she says. When the researchers looked at the 14 Lancet Commission risk factors, the group diverged in some way from the Canadian Longitudinal Study of Aging sample. For example, just 36 per cent were not meeting physical-activity recommendations (versus 83 per cent), but rates of some other risk factors, including depression, smoking history, and obesity, were higher in the Kimel Centre group. The Kimel Centre researchers also tested participants for uncorrected vision loss. “Even with glasses on, 16 per cent had poor vision,” Anderson notes.
The investigators assessed the degree to which participants’ habits changed as well as how closely they followed their personalized plan. “People did start engaging in more physical activity, but only among those with high adherence to their personalized program strategy,” Anderson says. “Brain-healthy eating improved overall, but especially among people with high or moderate adherence to their brain-healthy-eating strategy.
People became less depressed, but only among those with high to moderate adherence.” Levels of loneliness, anxiety, distress, and perceived stress decreased regardless of how closely people stuck to their program goals.
Finally, “global cognition is improving, but only among those with high to moderate adherence to their overall personalized program strategies,” Anderson says.
That relationship is important, she says, because it suggests that the improvement is not due simply to what’s known as “practice effect”—essentially just getting better at taking the test rather than experiencing real gains in brain function.
One thing that makes these results particularly exciting, Anderson says, is that, unlike such studies at the US POINTER, the interventions involved don’t require a lot of extra resources. “There’s no way a US POINTER trial could be implemented in regular community centres, because there were fixed exercise programs, fixed cognitive training, and fixed nutrition classes,” she says.
“Our model is not that way. We just tell people in which domains they’re at risk, and then they choose how to address it. That means we don’t have to train a bunch of community-centre staff because they’re already delivering these programs. Having people link their specific risks to what they choose to do in a community centre is the secret sauce of what we’re doing.”
Results from both the Kimel Centre and US POINTER studies are promising for another reason. “Some skeptics have said ‘Look, you can tell people about diet and exercise, but people don’t change their lifestyle,’” Chertkow observes. “Our indication at the Kimel Centre is that if you give people access to programs plus education, they will change their lifestyle.”
The Brain Economy
At the same time, “not everybody has equal opportunity to be able to do these things,” Sinha says. So-called social determinants of health, such as income, “can impact people’s ability to engage in this way.” For example, people from the Indigenous and Black communities may be less likely to seek preventive care due to distrust based on poor past experiences with the health-care system stemming from racial discrimination.
Financial resources can make an enormous difference in someone’s risk-factor profile, too. In a Canadian study that used methods similar to those of the Lancet Commission, researchers concluded that 58.7 per cent of dementia cases in the lowest household-income group (less than $20,000 annually) were potentially preventable, versus only 31.8 per cent in the highest income bracket (more than $150,000 per year).
But here, too, there’s reason for hope. “One of the things that came out recently was a study in the US in which they provided a food program for people who didn’t necessarily have access to healthy food, and it improved people’s brain health,” says Allison Sekuler, president and chief scientist at the Baycrest Academy for Research and Education in Toronto and the co-host of Baycrest’s Defy Dementia podcast.
“That shows there are ways we can address these issues.” One area in which Canada may be leading the way in doing so, Sekuler says, is through the new national dental-care program. “When your teeth are healthy, your whole body, including your brain, is more likely to be healthy,” she explains. “If you have an infection in your gums, it can lead to infection throughout the body, including the brain, which is potentially a risk factor for dementia.
And if you have problems with your teeth, you’re less likely to be eating healthy, and you’re less likely to be socializing.
“My message is that what’s been considered spending—taking care of people’s teeth and helping people with depression—is not spending; it’s investment in what we call the brain economy,” she says. “If you want everyone to contribute as much as possible to economic growth and prosperity, people need to be healthy. When you think about the cost of dementia, it’s not just the direct cost of care; it’s that people who are living with dementia are less able to contribute in the workplace. Every person who’s diagnosed with dementia comes with two or three people who are designated caregivers, who are also less able to contribute. And if you’re a caregiver for someone living with dementia, you’re up to six times more likely to develop dementia yourself, not because it’s contagious but because you get little sleep, you’re lonely, you’re isolated— you can’t do the sorts of things you could otherwise do to protect your brain health.”
All of these factors combined add up to a huge price tag. “The estimates of just how much dementia alone is costing our economy every year put the number at about $40 billion—about the same as the entire defence budget.”
Sekuler is optimistic. “We know so much more about dementia prevention and early detection that I think we’re headed towards a whole new era of what we would call ‘precision aging’—to make sure each person can get what they need to age as well as possible,” she says. “I feel we’re in one of the most hopeful periods that I’ve experienced in 30 years as an academic, in terms of what we can do to ensure that people can live and age with dignity, fulfillment, purpose, and good brain health.”
