Everyone knows that breathing bad air is bad for your respiratory health. But research suggests that the microscopic pollution we breathe in can cross the blood-brain barrier and harm our cognition.
“There’s a lot we don’t understand yet, but we do know that the risk of dementia increases in proportion to the amount of air pollution,” said Caleb Finch, a USC professor known for his work on Alzheimer’s and aging.
A study looking at how different pollutants impact the brains of mice exposed them to airborne particles for five hours. Dust from the World Trade Center was damaging, but diesel fumes were almost as bad. Both harmed more than 1,200 of the same genes and caused changes linked to Alzheimer’s in the brain. Wood smoke did not cause the same problems.
Clean air policies in New York City reduced pollution in the late ‘90s, making air significantly cleaner for pregnant women to breathe. A study using more than 1,000 mother-child pairs from 1998 to 2020 looked at cognitive development in children. From 1998 to 2020, the air in the mothers’ homes improved drastically, largely because of the New York City Clean Fuel Bus Program, Clean Air Taxi legislation, the Clean Heat Program and the Climate Mobilization Act.
Comparing the children born in the last wave of the study versus the first wave, kids’ Mental Development Index (MDI) scores improved 26 percent. Their MDI scores improved as the air quality improved.
If you’re an adult, you haven’t missed your window to improve your cognition. HEPA air filters can aid cognition. Using one in the home for a month aided brain function in adults over 40. A study used data from people aged 30 to 74 who lived between two major highways where the air quality was poor. People in the study either had a HEPA air filter or a placebo version where the filter was removed. They then took tests to measure visual memory, motor speed skills, executive function and mental flexibility.
People who were 40 and above completed the section on mental flexibility and executive function 12 percent faster after using the HEPA purifier. The researchers say that it’s possible longer use of air purifiers would improve cognition more. And, while the researchers hypothesized that the air purifiers helped people more as they got older, there weren’t enough people over 60 in the study to draw conclusions.
HEPA air filters can be surprisingly affordable. You can find reputable brands on Amazon as well as in local stores that making finding a good deal easier.
