Some of the biggest risk factors for memory impairments (a.k.a. dementia) are outside of our control, such as genetics and age (of the 5.8 million people in the U.S. with Alzheimer’s disease and related dementias, all but 200,000 are 65 or older). However, a growing body of research, including a new study published in Jama Neurology, suggests that certain lifestyle factors—things we can manage—might lower the risk of dementia, particularly earlier-onset dementia. Your response to some of these risk factors can help ward off or slow the condition’s progression.
Here, experts break down four big lifestyle-related risk factors for dementia, and how to mitigate them.
- ABOUT OUR EXPERTS: Dr. Verna R. Porter, M.D., is a board-certified neurologist and director of Dementia, Alzheimer’s Disease, and Neurocognitive Disorders at Pacific Neuroscience Institute. Dr. Jenna Stedman, D.C.N., R.D., C.S.S.D., is a doctor of clinical nutrition with Master Nutrition Lab. Dr. Ash Sharan, M.D., is a neurosurgeon and chief medical officer of neuromodulation at Medtronic. Dr. Lucy Andrews, D.N.P., is a doctor of nursing practice and the founder of Brain Guard System.
1. Eating Too Much Processed Food
Processed foods and sugary snacks and beverages have been associated with an increased risk of cognitive decline and dementia, according to Dr. Jenna Stedman, D.C.N., R.D., C.S.S.D., of Master Nutrition Lab. Why? “These foods can lead to inflammation, insulin resistance, and obesity, all of which are risk factors for cognitive impairment,” she explains.
In addition to limiting processed and high-sugar foods as much as possible, you can also support your brain long-term by incorporating certain foods known to help prevent cognitive decline. A few specific foods Stedman recommends emphasizing for healthy brain function include:
- Oily fish: Fish like salmon and sardines are rich in omega-3 fatty acids, particularly DHA (docosahexaenoic acid), which is crucial for brain health, she says. Omega-3s play a role in cognitive function and may help reduce the risk of age-related cognitive decline. If you’re not a big seafood eater, consider adding an omega-3 supplement rich in DHA to your daily routine.
- Whole grains: Quinoa, brown rice, whole-wheat pasta, and other whole grains provide a steady supply of glucose, which is the brain’s primary energy source (and a necessity for learning and memory). They also contain fiber, which helps regulate blood sugar levels (a must for healthy brain function), and B vitamins such as folate, which plays a role in neurotransmitter synthesis.
- Legumes: Chickpeas, black beans, and lentils are all rich in complex carbs, providing a steady release of glucose for sustained energy available to your brain (which, out of all of your organs, requires the most energy). While too much or too little sugar at once can pose problems for your brain, fiber-rich legumes keep things even, supporting good cardiovascular and metabolic health—and, in turn, helping to reduce the risk of dementia, Stedman says. Not to mention, legumes offer magnesium, folate, and iron, all of which are also important for brain health.
2. Poor Heart Health
Researchers believe heart disease is an independent risk factor for dementia—but it also ups the risk of stroke, which has also been implicated in increasing dementia risk. This is because poor heart health and strokes can both lead to vascular dementia, in which interrupted blood flow to the brain affects cognition by damaging brain tissue.
Diet and exercise are both major needle-movers for heart health, so the right strategy in these areas can support your cardiovascular system and ultimately work against dementia risk.
A few key ways to eat for better heart health: Swap seafood in for red meat, cut out or scale way back on ultra-processed foods, and eat more sources of soluble fiber (like beans, Brussels sprouts, or sweet potatoes with each meal).
Exercising is also great for your heart and lowering your dementia risk. In fact, one 2017 study showed a correlation between aerobic exercise and memory performance, finding that those who participated in activities that revved their heart, whether running, jumping jacks, or walking up and down the stairs, had a larger hippocampus (where short-term memory originates), notes Dr. Ash Sharan, M.D., neurosurgeon and chief medical officer of neuromodulation at Medtronic. “It’s very important to remain active to help slow cognitive decline,” he says.
3. Social Isolation
According to research published in the Journal of the American Geriatrics Society, socially isolated older adults are 27 percent more likely to develop dementia than those who are socially engaged. This could be because cognitive engagement goes down, potentially contributing to an increased risk of dementia, when opportunities to socialize with others are few and far between, the researchers suggest.
Having a circle of friends that you see regularly and who are deeply connected to you can help bridge social isolation, says Dr. Lucy Andrews, D.N.P., founder of Brain Guard System. “Additionally, joining a book club or learning a new hobby, such as painting or a new language—anything that engages your brain to create new neural pathways—helps build your brain in ways that decrease dementia risk,” she says.
If your people happen to live far away, don’t sweat it. The Johns Hopkins researchers behind that aforementioned study found that talking on the phone, texting, and communicating over email all lower the risk of social isolation. So lean into community digitally, if that’s what you have access to.
4. Falling Short On Vitamin D
A number of studies have looked at the connection between vitamin D and cognitive decline. One 2022 study published in the American Journal of Clinical Nutrition, for example, found that people with a vitamin D deficiency had a 54 percent greater chance of developing dementia compared to those getting enough of the vitamin.
Read More: 5 Possible Reasons Why You’re Not Absorbing Enough Vitamin D
What’s the connection? Vitamin D receptors are found throughout brain tissue and the vitamin has been shown to protect nerves from damage, in part by helping clear amyloid plaques, which disrupt cell function and are considered a hallmark of Alzheimer’s disease.
Known as the “sunshine vitamin,” your body gets its vitamin D primarily from the sun. That said, you’ll also find some in fatty fish like trout, salmon, tuna, and mackerel, as well as in beef liver, egg yolks, and cheese. The amount of vitamin D you need depends on your age, but the daily recommended amount for adults ages 19 to 70 is 15 micrograms, according to the National Institutes of Health.
If you’re not getting enough vitamin D from the sun or your meals, consider supplementing. After all, research has shown that doing so can help support brain health over time.
A simple blood test can give you a clear picture of your current vitamin D status and inform how much you might want to supplement with. (A healthcare provider can help you figure out the specifics.) Just note that since vitamin D is fat-soluble, any supplement will be best absorbed with a meal or snack that includes some fat.