TUESDAY, July 21, 2020 (HealthDay News) -- Regular exercise can reduce your risk of high blood pressure, even if you live in an area with high levels of air pollution, new research shows.
The new study included more than 140,000 adults in Taiwan who did not have high blood pressure and who were followed for an average of five years.
The researchers found that those who were highly active and exposed to low levels of air pollution had a lower risk of developing high blood pressure, while inactive people who were exposed to high levels of air pollution had a higher risk.
"Extended outdoor activity in urban areas increases the intake of air pollutants, which can worsen the harmful health effects of air pollution," said study author Xiang Qian Lao, an associate professor of public health and primary care at the Chinese University of Hong Kong in Shatin, Hong Kong.
For the study, the researchers looked at levels of exposure to fine particulate matter air pollution, which originates from fossil fuels and can be found in various sizes. PM2.5 are about 30 times smaller than the width of a single human hair, and can be inhaled into the deepest areas of the lungs.
Among the study participants, each increase in PM2.5 level was associated with a 38% increase in high blood pressure risk. But each increase in physical activity lowered that risk by 6%. The researchers said that suggests that reducing exposure to air pollution is more effective for preventing high blood pressure.
But regardless of pollution level, the benefits of regular physical activity remained. People who exercised moderately had a 4% lower risk than those who didn't exercise, and people who exercised at a high level had a 13% lower risk of high blood pressure than inactive people.
The findings were published July 20 in the journal Circulation.
The risk-benefit association between air pollution and physical activity is important because more than 91% of people worldwide live in areas where air quality doesn't meet World Health Organization guidelines, the study authors noted in a journal news release.
"While we found that high physical activity combined with lower air pollution exposure was linked to lower risk of high blood pressure, physical activity continued to have a protective effect even when people were exposed to high pollution levels," Lao said. "The message is that physical activity, even in polluted air, is an important high blood pressure prevention strategy."
The U.S. Centers for Disease Control and Prevention has more on preventing high blood pressure.