PFAS (per- and polyfluoroalkyl substances) are known as "forever chemicals" because their carbon-fluorine bonds are some of the strongest in chemistry, meaning they do not break down naturally in the environment and are very slow to leave the human body. While they do not stay "forever" in a literal sense, their half-life—the time it takes for the concentration to reduce by half—can range from several years to over a decade depending on the specific compound (such as PFOA or PFOS). In 2026, research from the NIH and other global health bodies highlights that these chemicals bioaccumulate, meaning if you are continuously exposed through contaminated water or food packaging, they can build up faster than your body can excrete them. Chronic exposure has been linked to altered metabolism, increased cancer risk, and immune system suppression. While some studies suggest that high-fiber diets or specific medical treatments like plasma donation might help lower blood levels, the primary focus in 2026 remains on regulation and filtration to prevent these persistent chemicals from entering the human body in the first place.