Clean air, sharper minds: HEPA purifiers boost cognition in adults over 40
A randomized crossover study of 119 people aged 30–74 in Somerville, MA found that using a real HEPA purifier for one month improved executive function/mental flexibility by about 12% in participants 40 and older compared with a sham purifier, after accounting for indoor time and stress. The small but consistent cognitive boost is similar to gains from daily exercise and highlights potential brain health benefits of reducing particulate exposure, especially for those near highways. Limitations include the short duration, modest older-subject representation, and unknown long-term effects or mechanisms; further research is planned to explore brain white matter and metabolite changes.
