Tongue numbness and yellow tongue coating may be physiological factors, but also may be the manifestation of certain diseases, such as tongue infection, digestive tract dysfunction, etc., should be timely consultation to find out the cause of the disease. 1. Physiological factors: If you eat greasy, spicy and stimulating foods, such as chili peppers, mustard, etc., your tongue will be stimulated by cold, acid, spicy and greasy, resulting in tongue numbness and yellow tongue coating. 2. Pathologic factors: (1) Tongue infection: after the tongue is infected, it will cause the cells of the tongue body to have stress reaction and immune reaction, which will affect the nervous system of the tongue body, resulting in numbness of the tongue, and cause pigmentation, resulting in the symptom of numbness of the tongue and yellow tongue coating. (2) Digestive tract disorders: When there are digestive tract disorders such as colitis, habitual constipation, dyspepsia, etc., anorexia, nausea, vomiting and other symptoms will occur when the gastrointestinal tract does not move well, and tongue malnutrition will lead to tongue numbness and yellow tongue coating. For people with yellow tongue and numb tongue, pay attention to maintaining oral hygiene in daily life, rinse your mouth in time before and after meals to avoid residual food debris, and develop the habit of brushing your teeth regularly. In terms of diet, pay attention to avoid eating spicy stimulating food, such as chili, mustard, etc.. However, other factors can not be ruled out, it is recommended to consult a doctor in a timely manner, by the doctor to clarify the cause of the disease, to give targeted treatment.