Excessive screen time can negatively affect physical health by promoting a sedentary lifestyle, leading to increased risks of obesity, cardiovascular diseases, and poor posture. Prolonged sitting can weaken muscles and contribute to chronic pain, particularly in the back and neck. Additionally, excessive screen time often correlates with inadequate sleep and can increase the likelihood of mental health issues, such as anxiety and depression. It's crucial to balance screen time with physical activity and regular movement to maintain overall health and mitigate these negative effects.