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Do Dietary Supplements Protect Against the Harmful Effects of Air Pollution Exposure?

Published March 12, 2018

Ground-level ozone, one of the six criteria air pollutants that are regulated by the EPA, is a molecule known to cause a variety of adverse health effects. EPA’s Our Nation’s Air report indicates that, while air pollution regulations have resulted in dramatic decreases in ozone levels over the past few decades, there are still people across the country living in areas with high levels of criteria air pollutants, including ozone.

EPA researchers are evaluating if dietary supplements can mitigate some of the adverse effects of ozone. In a recent study, researchers examined responses in rats exposed to ozone who had been fed different diets. Some were fed diets rich in fish oil containing high levels of omega-3 fatty acids while others were fed diets rich in other oils such as those from olives and coconuts. The results confirmed previous clinical studies that omega-3 fatty acids can provide some protection from pollution-induced vasoconstriction (tightening of the blood vessels). More research is needed to investigate if, how, and at what levels dietary supplements could protect public health.

Improvements in air quality over the last few decades have resulted in enormous health benefits for the United States. EPA researchers continue to investigate ways to reduce the impacts of air pollution, including how healthy diets and healthier living may extend these benefits even further.