A tongue that is half thick and half thin may be due to food irritation, tongue lesions or neuropathy of the brain. 1. Food irritation: long-term chewing and consumption of irritating food, such as betel nut, hot pot, etc. will cause irritation to the tongue, resulting in thickening of one side of the tongue. 2. Tongue lesion: Tongue inflammation, tongue tumor, and local edema after tongue injury can also cause thickening on one side of the tongue, and sometimes the patient will also have tongue pain, tongue bleeding and other symptoms. 3. Cerebral neuropathy: when patients have cerebral neuropathy, it will lead to nerve damage, causing symptoms such as facial paralysis, and after facial paralysis, it will make the muscles of one side of the face atrophy, resulting in thickening of one side of the tongue. Prolonged use of one side of the mouth for chewing can also lead to thickening of one side of the tongue, and the patient should consult a doctor in time.