Mouth ulcers are autoimmune diseases that have multiple causes and can develop when combined with local factors in the oral cavity. These factors include: psychological disorders, gynecological disorders, endocrine disorders, digestive system disorders, hematological disorders, after radiation therapy and chemotherapy for tumors, etc. Why are mouth ulcers prone to occur during the holiday season? What do we do during the holidays? Visiting friends and relatives, gathering, entertainment and singing, staying up late, watching TV, drinking, these are very different from our usual daily life habits. We know that the regularity of life has a great impact on the health of the human body, the daily routine is disrupted as a result of the body’s immune system balance is disrupted, which is a variety of diseases will come to the door! Long-term recurring mouth ulcers are generally not caused by oral diseases, common causes are: sleep disorders caused by immune system problems, dietary habits caused by nutritional deficiencies, gynecological diseases, endocrine system disorders (lipid metabolism, glucose metabolism) and so on.