Mewing

Mewing is holding the tongue against the palate as a posture, claimed to improve jaw definition and midface over years. The Mews are orthodontists with a contested clinical story. Forums treated mewing as a free jaw implant. Evidence for adult bone change is weak; evidence that mouth-breathing and a low tongue look worse is not.

House line: tongue posture and nasal breathing are cheap. Do not skip the gym and a haircut waiting for your mandible to migrate.