If the temperature is low during the day and normal at night, it is mainly considered to be caused by inflammatory diseases. It is more commonly caused by chronic bronchitis, bronchial dilatation, tuberculosis and other diseases, and also needs to be considered to be caused by tumors, connective tissue diseases and rheumatic diseases. You need to go to the hospital for routine blood tests, C-reactive protein tests, blood sedimentation and rheumatoid factor tests, chest X-ray, sputum test and tuberculin test. Through these tests to clarify the diagnosis, under the guidance of the doctor with drugs and active treatment. In normal times, we should pay attention to the light diet, try to avoid eating spicy, greasy, stimulating food, can eat more new vegetables and fruits, but also need to appropriate activities to improve the body’s resistance.