An alarming new study finds that 5.5 million people are dying every year from air pollution, with more than half of those deaths happening in China and India. But just because you don’t live in a city choked by smog every doesn’t mean air pollution isn’t doing a number on your body.

Research presented at the annual meeting for the American Association for the Advancement of Science indicates that air pollution is the fourth highest risk factor for death worldwide, and easily the biggest environmental risk factor, and therefore cutting air pollution should be a top priority for governments looking to improve the health of its populace, according to a Christian Science Monitor report.

We’ve all seen images of people walking around in Beijing with face masks as smog envelopes everything around them, but even those of us who live in cities where smog isn’t visible aren’t immune to the health effects of air pollution.

The problem with air pollution is that it has unseen effects on our bodies — at least until those problems manifest themselves later in our lives. Air pollution raises the rate of stroke, heart disease, and lung cancer.

There are steps you can take to avoid prolonged exposure to high amounts of air pollution, according to the American Lung Association. Check air pollution forecasts in your area and avoid exercising outdoors when the levels are high. Don’t exerise in areas with lots of traffic even on good air quality days.

You can also use less energy in your home. This means you’re doing your part to improve air quality overall, while also reducing the amount of air pollution in your general vicinity.