If you’ve ever seen a loved one struggling with dementia, you know it is a very tough experience for both the person with this condition and their loved ones. Dementia is not a specific illness; the Centers for Disease Control and Prevention (CDC) says it’s “a general term for the impaired ability to remember, think, or make decisions that interferes with doing everyday activities.” In 2014, the CDC estimated that about 5 million adults over age 65 had dementia and projected that that number will grow dramatically in upcoming decades. While we still have a lot to learn, research shows that there’s one activity worth limiting to reduce your risk of dementia. We spoke with dietitians to share what that activity is, how it increases your risk of dementia, and how to make changes to help you prevent this condition.
What is The #1 Activity to Limit To Reduce Your Risk of Dementia?
To reduce your risk of dementia, the best thing to limit is sedentary behavior. Any type of movement helps because a sedentary lifestyle is linked with an increased risk of dementia and other chronic diseases. Wan Na Chun (she/her), RDN, a registered dietitian nutritionist, says, “Research shows that exercise is a protective factor for these diseases, including dementia.”
For example, a 2023 study in the Journal of the American Medical Association (JAMA) found a significant association between sedentary behaviors and the risk of dementia in older adults. A 2020 study in Translational Psychiatry yielded similar results.
How Does A Sedentary Lifestyle Increase Your Risk of Dementia?
As you now know, research has found a link between sedentary behavior and dementia risk, but why does this association exist? Chun says, “While there is a strong association between dementia risk and sedentary behavior, more research is needed to determine whether the relationship is causal or associative.” In other words, most of the studies out there have found that older adults who were more sedentary over their lifetimes ended up with higher rates of dementia. However, these studies were observational; they weren’t experimental-style studies that could conclude that sedentary behavior causes dementia.
That being said, researchers have some ideas about why a sedentary lifestyle is linked with higher rates of dementia. Sharon McCaskill, M.A., RDN, founder of The Helpful GF: Gluten Free Living with Confidence, explains that a sedentary lifestyle impedes blood flow to the brain and disrupts the production of essential brain-supporting chemicals.
A 2021 study in Frontiers in Endocrinology found that aerobic exercise increased myokine Cathepsin B (CTSB) levels—a biomarker linked with cognitive function. Since some types of dementia are caused by reduced blood flow to the brain, physical activity is also helpful because it promotes healthy blood flow.
How Much Physical Activity Do You Need to Do?
Chun and McCaskill recommend following the physical activity recommendations set forth by the U.S. Department of Health and Human Services (USDHHS). For adults, the recommendations are at least 150 minutes of moderate-intensity aerobic activity each week or 75 minutes of vigorous-intensity aerobic activity. A moderate-intensity activity can be a brisk walk, whereas a vigorous-intensity activity can be going for a run. The guidelines also recommend that adults do muscle-strengthening activities for all major muscle groups twice weekly. “These recommendations will help drastically in lowering the risk of dementia but also in improving overall health and energy levels,” says Chun.
There are some additional considerations for older adults. If you have a chronic health condition, you should make adjustments. And if you can’t do the full 150+ minutes per week or you need to alter the types of activity you do, that’s okay. The idea is to move more while being mindful of what’s safe for you to do. Plus, the USDHHS recommends that older adults also incorporate balance training.
Even if these recommendations seem far-fetched right now, any movement helps. First and foremost, the USDHHS recommends moving more and sitting less throughout the day. In fact, a 2021 study in JAMA Network Open found that any increase in physical activity, even a low amount of light physical activity, was associated with a reduced risk of dementia in older Korean adults. Plus, a 2019 study in Alzheimer’s & Dementia found that just 10 minutes per day of moderate-to-vigorous physical activity was related to better cognitive function in older adults.
How to Move More
If you’re reading this and thinking that you’re quite sedentary, first of all, take a breath. It’s easy to get stressed about all you think you should be doing for your health, but making small changes can go a long way.
If 150 minutes seems overwhelming right now, just think about how you can find small bits of movement throughout your day. If you work a sedentary job, Chun recommends short walks during the day, like a 15-minute walk through your neighborhood or even just a 5-minute walk through your house. McCaskill suggests setting a movement timer to help you remind yourself to take these breaks.
Once you’re ready to incorporate more structured workouts, McCaskill says, “I recommend actually scheduling your activity to ensure you accomplish it. It can also help to schedule it with a friend and turn it into a social activity.”
It’s also helpful to experiment with different forms of exercise to see what you actually enjoy. Get creative. You may love dancing, rock climbing, running, biking, weight lifting, yoga, hula hooping, jumping rope or anything else that increases your heart rate.
The Bottom Line
Plenty of research has demonstrated that any amount of physical activity is linked with a lower risk of dementia, while a sedentary lifestyle may increase it. We still have much to learn about the mechanisms behind this relationship, but it’s worth sitting less in your day-to-day life to reduce your risk of dementia and chronic disease. To do so, you don’t have to stress about doing hour-long workouts every day; even taking breaks to go for short walks throughout the day helps. You may even want to try this Seated Flexibility, Cardio, & Strength Workout for an approachable yet effective workout.