Dementia, the degenerative brain disorder that generally affects older people, is a growing health challenge. The number of people with dementia is expected to rise to more than 150 million worldwide by the year 2050, an increase of almost 200% over today. The primary risk factor for developing the disease is simply getting older, but there are several easy things you can do every day to keep your brain healthy with age. These are 21 daily habits that increase your chances of developing dementia. One finding from a brand-new study may shock you.
A study recently published in JAMA found that men and women who sat for at least 10 hours a day had an 8% higher risk of developing dementia within the next seven years than if they sat for less than 10 hours. And all that sitting seems to override the benefits of exercise: People who worked out but sat at least 10 hours faced the same risk as people who did no exercise. You can lower your risk by finding ways to sit less. "People in our study who were sedentary for 9.5 hours a day didn't have any increased risk," said the study's lead author David Raichlen, a professor of biological sciences and anthropology at USC.
According to a September 2023 study published in The Lancet, people who work more physically demanding jobs—which "require considerable use of your arms and legs and moving your whole body, such as climbing, lifting, balancing, walking, stooping, and handling of materials—could be more likely to contract dementia. They include salespeople, nursing assistants, farmers, and livestock producers. The researchers speculate this could be because the jobs are tough on the body and mind and don't provide enough cognitive stimulation.
A 2018 study published in the journal Neurology found that people who lead high-stress lives may experience brain shrinkage and memory loss—even before they turn 50. "Higher levels of cortisol, a stress hormone, seem to predict brain function, brain size and performance on cognitive tests," said study author Dr. Sudha Seshadri, a professor of neurology at UT Health San Antonio. "We found memory loss and brain shrinkage in relatively young people long before any symptoms could be seen. It's never too early to be mindful of reducing stress."
Research published last summer in the Journal of Alzheimer's Disease found that Alzheimer's patients have about half the brain levels of antioxidants such as lutein, zeaxanthin, lycopene, and vitamin E—nutrients abundantly found in fruits and vegetables—as healthy people. "This study, for the first time, demonstrates deficits in important dietary antioxidants in Alzheimer's brains," said C. Kathleen Dorey, professor at Virginia Tech Medical School. "These results are consistent with large population studies that found the risk for Alzheimer's disease was significantly lower in those who ate diets rich in carotenoids… we believe eating carotenoid-rich diets will help keep brains in top condition at all ages."
According to recent research published in the medical journal Neurology, people who took proton pump inhibitors (PPIs) for acid reflux or other GI issues for more than 4.4 years had a 33% greater likelihood of developing dementia compared to those who didn't take the drugs.
Hypertension has been called the greatest risk factor for dementia, and having hypertension in midlife has been associated with a nearly 60% increased risk of developing dementia and 25% increased risk of Alzheimer's. A recent review of 17 studies published in JAMA Network Open found that people taking antihypertensive medications have a 26% lower risk of all-cause dementia than people who don't treat their high blood pressure.
A recent study from the National Institutes of Health found that long-term exposure to certain kinds of air pollution—including emissions from agriculture, wildfires, cars, and coal combustion—may produce a higher dementia risk. "There's several potential ways air pollution could affect the brain. One is through just inflammation that it causes in the lungs, in the body that may also enter the brain," said Dr. Charles Bernick, a neurologist with the Cleveland Clinic. "There's also the thought that the toxic properties of air pollution itself could directly enter into the brain."
In a 2021 study by University College London, researchers followed 8,000 50-year-olds as they aged. They found those who averaged six hours of sleep or less every night had a 30% higher chance of developing Alzheimer's, compared to people who got seven hours of sleep or more.
Research published earlier this year in the journal Alzheimer's & Dementia found that taking a vitamin D supplement was associated with a 40% lower risk of developing dementia over a 10-year period versus taking none. A 2022 study found that people with low vitamin D levels had a 54% greater chance of developing dementia compared with people whose levels were normal.
The chemicals in tobacco smoke can damage blood vessels and arteries, reducing circulation to the brain and raising dementia risk, experts say. One study found that smoking just one cigarette a day for an extended period can reduce cognitive ability, and smoking 15 cigarettes daily hinders critical thinking and memory by almost 2 percent.
Consuming too many foods high in sodium (such as packaged and processed foods) could lead to hypertension (a.k.a. high blood pressure). Over time, uncontrolled hypertension can damage small blood vessels in the brain, which can have an effect on thinking and memory, experts say.
Just like high blood pressure, having uncontrolled diabetes or chronically high blood sugar levels can damage blood vessels and nerves, raising your risk for dementia, heart disease and stroke.
Several studies have found that higher levels of daily physical activity are associated with a lower risk of Alzheimer's. Exercise helps promote brain plasticity and increases blood flow to the brain, experts say. Just 10 minutes of moderate exercise three to four times a week has been shown to benefit the brain.
A July 2023 study published in JAMA Open found that older adults who frequently engaged in brain-challenging activities, such as puzzles, games like chess, or journaling, had a lower risk of developing dementia.
Chronic loneliness causes a stress response in the brain and throughout the body. According to a study published in the journal Antioxidants and Redox Signaling, that creates long-term inflammation which can lead to cardiovascular disease, cancer, and dementia. "Staying socially engaged may support brain health," the Alzheimer's Association says. "Pursue social activities that are meaningful to you. Or just share activities with friends and family."
According to a study that followed 398,000 people up to 12 years, those who reported drinking more than six cups of coffee a day had a 53% higher risk of dementia and smaller brain volume than people who drank less. But take note: Moderate coffee consumption has been associated with multiple health benefits, including a lower risk of heart disease, several cancers, Alzheimer's, and Parkinson's. "As with most things in life, moderation is the key. Very high coffee intakes are unlikely to be good for you," said the study's author.
A long-term study of nearly 16,000 people published in the journal JAMA Neurology found that people who had the highest rates of vascular illness (including diabetes and high blood pressure) also had the highest risk of developing dementia. "A healthy cardiovascular system keeps blood vessels open, allowing good blood flow to the brain and reducing the risk of high blood pressure, stroke and dementia," the Washington Post explained this week.
Research published in The Lancet last July found that people with a greater risk of cognitive decline who were fitted with hearing aids had a 48% lower risk of developing dementia than those who didn't get the devices. Researchers think hearing loss might cause dementia by sending garbled signals to the brain, causing the organ to atrophy, or encouraging people to stop pursuing mental and social stimulation.
According to a study published in the journal JAMA Internal Medicine, older people who have cataracts removed are nearly 30 percent less likely to develop dementia, including Alzheimer's, than people with cataracts who don't get the surgery. Several other studies have found that vision impairment is associated with an increased risk of dementia. Researchers believe a person who has trouble seeing is less likely to keep the mind active by reading, watching movies and TV, playing games, and socializing with other people.
A 2012 study published in PLOS Medicine found that having a healthy lifestyle (that is, one that follows recommendations about smoking, alcohol consumption, weight, diet and exercise) can lower your risk of cognitive impairment by 55%. This was true even among people with an increased genetic risk of dementia.
A study published in JAMDA: The Journal of Post-Acute and Long-Term Care Medicine found the more teeth a person had lost, the greater their risk of developing dementia or cognitive decline. For every tooth lost, a person had a 1.1% greater risk of developing dementia and a 1.4% greater risk of experiencing cognitive decline. Researchers speculate that lingering oral bacteria can cause chronic inflammation, including in the brain.
