Yin deficiency is caused by a deficiency of vital fluids such as body fluids, essence, and blood, leading to insufficient Yin in the body. This results in a diminished ability to nourish and control yang heat, causing the imbalance of Yin and Yang, which manifests as dryness, heat, and other symptoms. In Chinese Tongue Diagnosis, Yin deficiency often appears as a red tongue with little or thin coating, and the tongue may show cracks, indicating severe Yin fluid deficiency in the body. The tongue appearance is a crucial tool for diagnosing this condition. 1. What Are the Symptoms of Yin Deficiency? Yin deficiency leads to a lack of body fluids, causing the body to lose the necessary moisture and nourishment. Through Chinese Tongue Diagnosis, one can observe that a person with Yin deficiency may have a red tongue, a thin or absent coating, and the tongue may appear dry or…