The examination of the lingual surface offers a diagnostic tool within Traditional Chinese Medicine (TCM). Visual assessment focuses on color, shape, coating, and texture variations across different areas. These variations are believed to correspond to the functional status of specific organ systems and meridians within the body. For example, redness at the tip might indicate heat in the heart, while a thick, greasy coating across the center could suggest digestive imbalances.
This diagnostic method’s value lies in providing a non-invasive way to gain insights into internal physiological processes. Its usefulness stems from its potential to identify imbalances before they manifest as overt disease symptoms. The practice has ancient roots, evolving over centuries through clinical observation and theoretical refinement. It’s considered a valuable adjunct to pulse diagnosis and other TCM diagnostic techniques.