Most people eat a mixed diet of foods from plants and animals. In most societies, starchy staple foods,
particularly cereal grains, are the main source of energy in the human diet. In certain areas, especially in the
humid tropics, root and tuber crops, together with plantains and similar plants, are either the staple food or a
supplement to cereal staples.
Fruit and vegetables are important sources of essential minerals and vitamins in the human diet. When eaten together with some root (potato, sweet potato) and leguminous (pigeon peas, beans, lentils) crops, they provide a
proportion of protein requirements as well as variety in flavour and colour.