In a murine model of iodine-induced autoimmune thyroiditis, a ketogenic diet reduces serum levels of malondialdehyde and increases serum levels of superoxide dismutase and total antioxidant capacity.

When the body burns fat for fuel instead of sugar, it produces a molecule called beta-hydroxybutyrate that stops damaged thyroid cells from releasing a danger signal called HMGB1. Without this signal, immune cells do not activate a destructive protein complex called NLRP3, which normally triggers inflammation and cell damage. This reduces the release of inflammatory chemicals that attract immune cells to the thyroid, lowers the production of harmful free radicals, and allows the body’s natural antioxidant systems to recover. At the same time, the immune system shifts from attacking the thyroid to calming down, which further reduces tissue damage and oxidative stress.