Weight loss refers to the reduction of total body weight, which can include loss of fat, muscle, or water. It typically occurs when the body burns more calories than it consumes, creating a calorie deficit. Weight loss can be intentional, through diet, exercise, and lifestyle changes, or unintentional, due to medical conditions or stress. Intentional weight loss is often pursued to improve health, manage chronic conditions, or enhance physical fitness. Sustainable weight loss focuses on gradual changes, emphasizing balanced nutrition, regular physical activity, and long-term habits for overall well-being.