Occasionally staying up late does not affect much, but long-term staying up late has many harmful effects on the body, staying up late tends to affect the normal function of the body and affects health, as follows: 1. Staying up late is harmful to the digestive system, staying up late for a long time will lead to gastrointestinal crisis, bloating, diarrhea, nausea, constipation, etc.. Staying up late is prone to cancer, because cancer cells are caused by cell division, and cell division usually occurs during sleep, staying up late will make cells divide abnormally, leading to cell mutation and cancer cells. 2. Staying up late will also have a greater impact on the cardiovascular system, resulting in chest tightness, shortness of breath, palpitations, etc., which can seriously lead to sudden death. 3. Staying up late is also harmful to the kidneys, leading to kidney deficiency, hair loss, waist and knee weakness, etc. 4. 4, damage to the eyes, easy to appear visual fatigue. 5, the skin condition will also become worse, appear skin slack, bags under the eyes, wrinkles, etc., long-term stay up late will cause autonomic nerve dysfunction, will appear neurosis, etc..