Researchers have discovered that human gut bacteria can bioaccumulate per- and polyfluoroalkyl substances (PFAS), widely known as 'forever chemicals' that persist in the human body and environment causing health risks. Experimental studies demonstrated bacteria such as Bacteroides uniformis sequester PFAS at millimolar levels, and mouse models showed these microbes reduce systemic PFAS exposure by filtering and expelling the toxins through feces. This unexpected mechanism opens the potential for gut microbiome-based interventions to mitigate PFAS’s harmful impact, a major advance considering PFAS’s widespread presence and influence on diseases including infertility, cardiovascular conditions, and cancer.