You can eat egg custard when you cough and have phlegm. When coughing and coughing phlegm occur, the diet is recommended to be light and you can eat fresh vegetables and fruits. In addition, foods that are too spicy, stimulating and greasy can help dampness and produce phlegm, which can stimulate increased phlegm secretion and is not conducive to symptom recovery. Attention should be paid to making corresponding lifestyle adjustments. At the same time, a comprehensive examination and evaluation should be conducted to identify the causes of cough and phlegm and provide appropriate treatment. If bacterial infection is considered to be combined, anti-infective treatment should be given to better control the clinical symptoms of the patient.