April 29, 2015 1:25 PM EDT
L ong-term exposure to air pollution may cause your brain to age more quickly and put you at higher risk for a stroke, a new study suggests.
Exposure to higher levels of air pollution may be linked to lower total cerebral brain volume, according to a study published in the May issue of Stroke, which analyzed health data from nearly 1,000 men and women over 60 who did not have dementia and had not had a stroke.
Total cerebral brain volume naturally decreases as humans age, resulting in declines in ability to learn new things and retrieve information, but the researchers found that air pollution exposure may be linked to premature brain aging and higher risks for certain brain strokes.
The findings add new knowledge to the impact of air pollution on the structure of the brain, a link that has remained largely unclear in research.
See the Worst Place to Breathe in America A passenger train travels through town past a refinery in Bakersfield, Calif. Lexey Swall—GRAIN Oil pumps and scarred earth can be seen for miles in an area of North Bakersfield called the Bluffs. A Cogeneration Plant sits in the middle of the fields and is one of California's top polluters. Lexey Swall—GRAIN A dust storm blows through Bakersfield, Calif. Dust is a pervasive problem in the area. Lexey Swall—GRAIN Yareli Gonzalez, 7, suffers from asthma and receives two nebulizer treatments per day, indefinitely. Gonzalez lives in Shafter, a rural farming town in Kern County, Calif. Kern County sits at the southern end of the San Joaquin Valley, an area known for having the worst air in the nation due to dust, smog and high levels of ozone. Lexey Swall—GRAIN Asthma educator Sharon Borradori, left, shows Margarita Hernandez, center, and her husband, Severo Velasco, right, how their 2-year-old son, Mauricio Velasco will use an inhaler when he's older. Mauricio was recently released from the hospital after suffering from an extreme asthma attack. Lexey Swall—GRAIN Children practice sports on a field at Bakersfield High School which backs up against the train yard that runs through the middle of town in Bakersfield. Lexey Swall—GRAIN Young football players exercise on the stadium of Bakersfield High School. Bakersfield High is the oldest high school in town and the mascot, the Driller, is directly tied to area industry. Lexey Swall—GRAIN Benjamin Swall, 14, waits for his brother's football practice to end at Bakersfield High School. Lexey Swall—GRAIN Red Simspon, a country music legend and Bakersfield native, smokes a cigarette outside of the Rasmussen Senior Center in Oildale, north of Bakersfield. Lexey Swall—GRAIN Merced Mendoza moves irrigation pipe in a field that will be used to grow alfalfa. The field is adjacent to and owned by Kern Oil and Refining Co. Mendoza is a leader for a men's group at Victory Outreach Church in Bakersfield that rents the land from the refinery to grow alfalfa that is then sold to a local dairy for feed. The money earned from the feed helps fund the men's program for the church. This symbiotic relationship between resource companies and the community are played out throughout the region. Lexey Swall—GRAIN Percolation ponds fill up with runoff water from nearby Belridge Oil Fields in Eastern Kern County. As the water evaporates, leaving oil residue, hydrogen sulfide, methane and volatile organic compounds, or VOCs, are released in to the air. Lexey Swall—GRAIN Dust devils can be seen reaching toward the sky during dry months in Bakersfield. Dust is a pervasive problem that contributes to diminished air quality. The problem is exacerbated by the current drought in California. Lexey Swall—GRAIN Lucy Clark, 72, lives in the foothills north of Bakersfield. Her home sits at 2200 feet, which is about the elevation where the visible layer of smog begins to hang in the air. Because of this, Clark, who suffers from asthma, wears a mask every day she walks out to get the mail. Lexey Swall—GRAIN Elk Hills Power plant provides electricity to power Occidental Elk Hills oil field. Oxy's Elk Hills field is one of the largest oil fields in the United States and the natural gas power plant can produce 550 megawatts of electricity. Lexey Swall—GRAIN Samantha Olivarez, 9, left, and her cousin, Daisy Olivarez, 7, play in front of their home in Arvin, Calif. The homes across the street were evacuated after a gas pipe leaked underground. According to reports, the 40-year-old pipe was leaking for as long as two years before it was detected. Olivarez's family is worried about possible health risks in the area due to the pollution. Lexey Swall—GRAIN Specifically, a 2 microgram per square meter increase in PM2.5 (particulate matter in the air that is less than 2.5 micrometers wide) was associated with a 0.32% lower total cerebral brain volume, the study said. To put that in context, brain volume decreases at about 0.5% per year after age 40, and PM2.5 levels can vary widely across the world. For example, the PM2.5 in Beijing is about 175 micrograms per square meter, while the PM2.5 in New York City is about 30 micrograms per square meter.
See the 10 Healthiest Cities to Live in America Honolulu, Hawaii Best Place for Lifelong Health The heavenly climate helps, but the key to well-being here also includes enviable health care and a rich cultural tradition of looking out for one another. Colin Anderson—Blend Images/Corbis San Francisco Bay Area, Calif. Best Place for Eating Right. The "farm to table" movement began here. The region's bounty of produce and year-round growing season make eating healthy—and local—a natural. Getty Images Burlington, Vt.
Best Place for Raising Healthy Kids
This New England city offers great schools, excellent pediatric care, loads of culture and limitless options for healthy outdoor fun all year long.Matt Hogan/www.mphoganphoto.com Silicon Valley, Calif.
Best Place for Workplace Wellness
With treadmill desks, meetings on bikes, time off for creativity, and gobs of organic food, tech titans are reinventing how to stay healthy on the job.Jim Wilson—The New York Times/Redux Minneapolis-St. Paul, Minn.
Best Place for Aging Well
Yes, it can be cold. But with a plethora of stimulating activities and a robust web of support, the Twin Cities prove that growing old doesn't mean slowing down.Getty Images Denver and Boulder, Colo.
Best Place for Keeping Fit
The urge to get outside and get moving is contagious in these Rocky Mountain cities, where physical challenge is built into the landscape.Celin Serbo—Aurora Photos/Corbis Plano, Texas
Best Place for Staying Safe
Once a rural outpost, this booming, diverse city has kept its small-town vibe, thanks in part to a police force and community that knows how to work together.Misty Keasler—Redux for TIME Portland, Ore.
Best Place for a Healthy Environment
Small, walkable neighborhoods, 300 miles of bike paths, and urban policies that foster active living and sustainability make for one clean, green city.Getty Images Boston, Mass.
Best Place for Health Care
This history-rich city is home to some of the nation's most advanced medical institutions and policies that help ensure that quality care is available to all.K.C. Cohen—Courtesy of Boston Children's Hospital Provo and Orem, Utah
Best Place for Spiritual Well-Being
A stunning Rocky Mountain backdrop and a tight-knit population that lives its faith contribute not only to this region's serenity but also to lower rates of disease.Getty Images More Must-Reads from TIME Donald Trump Is TIME's 2024 Person of the Year Why We Chose Trump as Person of the Year Is Intermittent Fasting Good or Bad for You? The 100 Must-Read Books of 2024 The 20 Best Christmas TV Episodes Column: If Optimism Feels Ridiculous Now, Try Hope The Future of Climate Action Is Trade Policy Merle Bombardieri Is Helping People Make the Baby Decision