A high-calorie diet is a nutritional plan that includes a greater number of calories than the average daily requirement. This type of diet is often used by individuals looking to gain weight, such as athletes or those recovering from illness. Foods rich in calories typically include nuts, avocado, dairy products, and whole grains. While high-calorie diets can be beneficial for some, they must be balanced with essential nutrients to ensure overall health. It's important to focus on quality calories, meaning that the diet should include a variety of fruits, vegetables, and proteins to support bodily functions and prevent deficiencies.