Food is any substance consumed to provide nutritional support for an organism . Food is usually of plant , animal , or fungal origin, and contains essential nutrients , such as carbohydrates , fats , proteins , vitamins , or minerals . The substance is ingested by an organism and assimilated by the organism's cells to provide energy , maintain life, or stimulate growth. Different species of animals have different feeding behaviours that satisfy the needs of their unique metabolisms , often evolved to fill a specific ecological niche within specific geographical contexts. https://en.wikipedia.org/wiki/Food