What are some common tongue diagnoses? See a U-shaped coating at the back? That supposedly correlates to toxins in your colon. Discolored areas to the side and back? That may be a kidney problem. A reddish spot toward the front? That’s an overworked heart.
Yikes, this is all sort of scary-seeming. There’s more: If your tongue has cracks in it, is shaking or has a deep ridge in the center, you might have deep-seated emotional disturbance.