This Type Of Toxic Exposure May Disrupt Mitochondrial Function

You can usually tell when the air outside isn't great. Maybe the sky looks hazy, your throat feels irritated, or you decide to skip your usual outdoor run. But polluted air doesn't stop affecting you once you head back inside.

Researchers are starting to look at what happens deeper in the body, including whether air pollution changes how our cells use energy.

In a recent study, scientists found changes in the way people exposed to higher levels of pollution processed fat, offering a new clue about how polluted air may affect the body.

About the study

Mitochondria help our cells turn nutrients from food into energy. They also help the body use fat for fuel, so problems with mitochondrial function can affect how efficiently cells handle energy.

Earlier research in animals found that diesel exhaust exposure could change blood fats and affect mitochondria in the liver. Researchers wanted to see whether people exposed to higher levels of air pollution showed similar changes.

They studied two groups. Mice were exposed to either diesel exhaust or filtered air for two weeks.

They also followed 26 healthy adults who moved from Los Angeles to Beijing for 10 weeks, where they experienced much higher levels of fine-particle pollution.

Researchers analyzed blood samples from both groups, looking for changes in molecules involved in fat metabolism and oxidative stress.

Pollution may make it harder for cells to use fat

The mice and humans showed similar changes in how the body was processing fat. One of the clearest clues involved compounds called acylcarnitines, which can build up when cells aren't breaking down fatty acids efficiently.

The mouse results gave researchers a closer look.

The people exposed to higher pollution levels also showed changes linked to fat damage and exposure to pollutants commonly produced by vehicle exhaust and other combustion sources.

That doesn't mean the study proves air pollution causes mitochondrial dysfunction in people.

The human group was small, and researchers measured changes in the body rather than following participants over years to see whether they developed disease.

Another way pollution may affect heart health

Inflammation is one of the better-established ways air pollution can affect cardiovascular health. Polluted air can promote inflammation and changes in blood vessels that contribute to plaque buildup and heart disease.

This study suggests there may be another piece to the story. If pollution makes it harder for cells to process fat and produce energy, it could add to the metabolic stress caused by long-term exposure.

Researchers still need to determine what these cellular changes mean for people's health over time. But the findings give scientists another possible pathway to investigate.

A few ways to reduce your exposure

You can't control the air quality outside, but you can be strategic about when you spend time in it.

The takeaway

Air pollution may be putting extra strain on the body's energy systems, not just the lungs and blood vessels.

The research is still early, but checking the AQI before heading outside is an easy way to make more informed choices about exposure.