Developing dementia is a common fear. While most people experience at least some forgetfulness with age, dementia can interfere with your daily life and make it increasingly difficult to think clearly and perform activities. There are nearly 10 million new cases globally each year, according to the World Health Organization.
Dementia is not a single disease, but refers to brain changes that result in progressive loss of memory and impaired cognition. There are different types, including vascular dementia, which is often caused by strokes, and Alzheimer’s disease dementia, the most common and well-known.
Some people are more likely to develop dementia due to factors that can’t be controlled, such as their genes or age. (A person’s risk goes up starting at age 65; by 85, one in three people are living with Alzheimer’s.)
There’s a lot still to learn about how, exactly, dementia develops, says Dr. Kristine Yaffe, a distinguished professor of psychiatry, neurology, and epidemiology, and director of the Center for Population Brain Health at the University of California, San Francisco. “Experts debate about how many risk factors there are, as the field is evolving,” she says. But research suggests there are certain strategies you can adopt across your lifespan to potentially lower your risk, even if you have a family history of dementia or one of the genes linked to Alzheimer’s.
In July 2026, the World Health Organization released updated guidelines on modifiable risk factors that may reduce risk of dementia and cognitive decline: by addressing them all, 45% of dementia cases could be prevented, the authors estimate. The guidelines closely align with a 2024 update to the Lancet Commission on dementia prevention, which identified 14 modifiable risk factors for dementia. “Just because it’s quite common doesn’t mean it’s inevitable,” says Dr. Jason Karlawish, a professor of medicine, medical ethics and health policy, and neurology at the University of Pennsylvania Perelman School of Medicine and fellow of the University of Pennsylvania’s Institute on Aging.
Not every case of dementia is preventable. Sometimes “there is such bad luck,” notes Yaffe. Some people will follow healthy habits for many years and still develop it. “We don’t want to put blame on people, or have people feel like it’s entirely in their control,” she says. “But I do think there's a message of hope that being able to change some of these things actually could delay or minimize your risk.”
These healthy habits benefit your whole body—including your brain—and may help contribute to lower dementia risk over time.
Prioritize your heart health
What you can do: Aim for 150 minutes of moderate-intensity exercise a week, take prescribed medications, and follow a heart-healthy diet. (The American Heart Association recommends a variety of fruits and vegetables, whole grains, and healthy protein sources, and limiting saturated fats, sugars, sodium, and ultra-processed foods.)
A number of dementia risk factors “bundle together quite nicely,” notes Karlawish: High LDL cholesterol, obesity, hypertension, physical inactivity, and Type 2 diabetes account for 14% of potentially modifiable risk, according to the Lancet Commission. “Anything that you think about that might be harmful for the heart—like hypertension, obesity, diabetes, high lipids—all of those things turn out to actually be important for brain health, too,” says Yaffe.
In a large longitudinal study published in the European Heart Journal, people with higher blood levels of troponin I, a protein released when the heart experiences damage, were more likely to develop dementia later on. Heart failure, atrial fibrillation, and coronary heart disease were linked to cognitive impairment and increased dementia risk in a 2024 scientific statement from the American Heart Association published in the journal Stroke.
These five risk factors are deeply interconnected, notes Karlawish: Obesity increases a person’s risk for developing high LDL cholesterol, hypertension, and Type 2 diabetes, for example, while getting enough physical activity can lower the risk of all these conditions.
“The good thing is the vascular risk factors are very, very treatable,” says Dr. Joseph Coresh, founding director of the Optimal Aging Institute at the NYU Grossman School of Medicine. “But we may need to treat them quite early to get the maximum benefit.” That includes staying physically active; eating a heart-healthy diet; maintaining regular check-ups to monitor blood pressure, cholesterol levels, and glucose; and taking prescribed medications to manage these conditions.
Don’t smoke and limit your alcohol intake
What you can do: Quit smoking and consume no more than two alcoholic drinks per day (for men) and one alcoholic drink per day (for women).
Smoking accounts for 2% of modifiable dementia risk, according to the Lancet commission, and heavy alcohol consumption accounts for 1%. The recent World Health Organization guidelines also urge adults to stop smoking and reduce their alcohol intake. Both of these habits also tie into vascular risk, since studies have shown that smoking and excessive alcohol (which the American Heart Association defines as more than three drinks per day) may increase the risk of cardiovascular disease.
Excessive alcohol can also be a “slippery slope” for your overall health, adds Coresh. “Alcohol has calories, and alcohol has effects on sleep, and alcohol has an effect on drinking more alcohol—which then has an effect on injuries.”
There are plenty of other reasons to quit smoking and drink in moderation, if it all. Smoking impacts every organ in the body and contributes to an estimated 480,000 deaths in the U.S. each year, while excessive alcohol can harm the liver (along with other organs) and increase the risk of many types of cancer.
Stay socially connected
What you can do: Stay in touch with friends and family, volunteer, and join local social groups.
“Social frailty,” which means having few connections with friends and family, has been associated with an increased risk of dementia. In addition to prioritizing physical activity, continuing to focus on social connections as you age seems to support your long-term brain health, says Yaffe. “There’s pretty good evidence that staying active is a way to prevent getting cognitive changes and dementia,” she says. The new World Health Organization guidelines recommend cognitive training, cognitive stimulation, and participation in a variety of social activities for adults with both normal cognition as well as mild impairment.
The benefits of social connectedness may be even more pronounced when combined with other brain-healthy habits. In the U.S. POINTER clinical trial, which was published in JAMA in 2025, researchers evaluated different dementia lifestyle interventions in a group of people who were at higher risk of developing dementia. Combining two interventions—such as regular physical activity, following the MIND diet, or participating in socially engaging activities like spending time with peers—resulted in cognitive improvement at the end of the two-year period.
“They did not study whether that improvement reduced risk of developing dementia,” notes Karlawish. However, “they showed that if you do these activities, you can improve your cognition, particularly your ability to multitask and problem-solve in these executive functions.”
Care for your vision and hearing
What you can do: Stay on top of doctor’s appointments, and don’t wait to get help if you think you’re experiencing vision or hearing loss.
Having trouble hearing or seeing properly can accelerate cognitive decline. Hearing loss is one of the biggest individual risk factors in the Lancet commission’s list, representing 7% of modifiable risk. Vision loss, with 2% risk, was added in the latest update.
You can start protecting your auditory health in midlife, such as by limiting your exposure to loud noises and using noise-canceling headphones, says Karlawish. Habits like these “certainly can reduce the risk later on of hearing loss,” he says.
If you do start to experience hearing loss, there’s evidence that getting hearing aids sooner rather than later can benefit your cognitive health, especially if you have a higher risk of developing dementia. In a randomized clinical trial called the ACHIEVE study, which Coresh co-authored, researchers found that hearing aids reduced cognitive decline over a three-year period for some groups. “People at high risk for cognitive decline benefited tremendously,” he says.
People with lower risk did not experience sufficient cognitive decline to see benefits within the three-year period, but they “benefited in terms of social isolation, fall risk, and feeling that they had a lower hearing handicap,” he explains.
Vision has more recently been identified as a possible risk factor. “Treating vision loss has benefits for vision and for function,” says Coresh, though more research is needed. “We’ve only seen what’s called observational data,” he notes, such as in a 2021 meta-analysis, where researchers found an increased risk of dementia among those with impaired vision.
Improve the quality of your sleep
What you can do: Aim for at least 7 hours a night, and let your provider know if you’re having trouble sleeping.
It wasn’t included in the most recent Lancet commission update, but “sleep is gaining more and more importance,” says Coresh. Poor sleep has been associated with cardiovascular disease, he says, which means “one can recommend good sleep for good heart health, and by translation good brain health.” The World Health Organization guidelines note that while there’s insufficient evidence to recommend sleep interventions for cognitive decline, getting plenty of deep, restorative sleep is a critical part of overall health and well-being.
Though more research is needed, studies have also linked sleep quality to cognitive health, Yaffe points out. “I think the evidence for sleep is actually quite strong,” she says. For example, when you deprive animals of sleep in scientific studies, “you get an accumulation of tau and amyloid proteins, which are the hallmarks for Alzheimer's.”
Other research has found an association between sleep and dementia. In a 2026 paper Yaffe co-authored, in which she followed the same group of people for decades and asked them how long and well they slept, those who had reported poor sleep in midlife were more likely to have evidence of Alzheimer’s disease 20 years later.
Follow a balanced diet
What you can do: Focus on whole grains, leafy green vegetables, berries, nuts, beans, poultry, and fish, and limited saturated fat foods such as pastries and red meat.
Diet wasn’t always thought of as being an important risk factor for dementia, says Yaffe, “but in the last 10 years, there’s increasing evidence that having a healthy diet like the Mediterranean diet seems beneficial.” The updated World Health Organization guidelines now strongly recommend a healthy balanced diet to reduce the risk of cognitive decline. “There’s no doubt in my mind that diet is incredibly important,” adds Coresh.
The new guidelines don’t specify a particular diet to follow. But one eating plan believed to offer brain-health benefits is the MIND diet, which combines aspects of the Mediterranean and DASH diets. Researchers from Rush University Medical Center and the Harvard T.H. Chan School of Public Health published two papers in 2015 showing that slower rates of cognitive decline were associated with a diet that limits saturated fat and promotes vegetables, whole grains, nuts, beans, fish, berries, lean proteins, and olive oil—leading them to recommend these foods for better cognitive health.
Along with exercise, a balanced diet also supports a healthy lifestyle, notes Yaffe—in turn helping to manage other modifiable dementia risk factors such as cardiovascular disease, obesity, diabetes, and hypertension.