Does chewing gum or grinding teeth release more mercury from amalgam fillings?

What's actually in it

Amalgam fillings are about half elemental mercury. The metal is locked into a hard alloy with silver, tin, and copper. Most days the filling sits there fine. But friction breaks tiny amounts loose. Chewing, brushing, and grinding all rub the surface. The mercury comes off as vapor. You breathe it in, and it joins the mercury already in your blood.

What the research says

A 2026 study in Clin Chem Lab Med measured blood mercury in American adults and counted their amalgam surfaces. People with more fillings had higher mercury. The bump was bigger in gum chewers and people who grind their teeth at night. Old fillings that were cracked or worn leaked more than fresh ones.

Don't rip out healthy fillings. The drill itself releases a big mercury burst. If a filling needs replacing, find a dentist trained in SMART removal (rubber dam, high-volume suction, supplemental air). Cut back on gum, especially sugar-free gum that you chew for hours. Get a night guard if you grind. New cavities can be filled with composite or ceramic.