Staying up late to read novels is an unhealthy behavior that has a negative impact on both physical and mental health. Staying up late can cause harm to the body because staying up late can cause physical fatigue and lack of sleep, affecting the body's immune system, metabolism system, and cardiovascular system. Staying up late for a long time could also lead to problems such as lack of concentration, memory loss, and physical coordination. Staying up late to read novels would affect mental health because staying up late would make the brain unable to rest sufficiently, resulting in slow thinking, mood swings, anxiety, and other problems. Over-reliance on novels would also make it impossible for one to focus on other things, resulting in social isolation and emotional stress. Therefore, we should try our best to avoid staying up late to read novels, maintain adequate sleep and a balanced diet to keep our bodies and brains healthy. At the same time, we should also pay attention to controlling the time and frequency of reading novels to avoid the negative effects of being addicted to novels on our physical and mental health.