Animal fats are foods high in calories (900 calories per 100g). Then, vegetable oils and certain seeds such as walnuts contain a lot of calories. Dark chocolate-butter is also a food high in calories with close to 500 calories per 100g.
Foods high in calories are those that provide the most energy to our body. These foods are essential because they maintain the vital functions of our organism. But eating too much of these foods high in calories without exercise, can lead to obesity and increases risk of cardiovascular disease.