Home cooking has traditionally been a process carried out informally in a home or around a communal fire, and can be enjoyed by all members of the family, although in many cultures women bear primary responsibility.[46] Cooking is also often carried out outside of personal quarters, for example at restaurants, or schools. Bakeries were one of the earliest forms of cooking outside the home, and bakeries in the past often offered the cooking of pots of food provided by their customers as an additional service. In the present day, factory food preparation has become common, with many "ready-to-eat" foods being prepared and cooked in factories and home cooks using a mixture of scratch made, and factory made foods together to make a meal. The nutritional value of including more commercially prepared foods has been found to be inferior to home-made foods.[47] Home-cooked meals tend to be healthier with fewer calories, and less saturated fat, cholesterol and sodium on a per calorie basis while providing more fiber, calcium, and iron.[48] The ingredients are also directly sourced, so there is control over authenticity, taste, and nutritional value. The superior nutritional quality of home-cooking could therefore play a role in preventing chronic disease.[49] Cohort studies following the elderly over 10 years show that adults who cook their own meals have significantly lower mortality, even when controlling for confounding variables.[50]

Most food has its origin in plants. Some food is obtained directly from plants; but even animals that are used as food sources are raised by feeding them food derived from plants. Cereal grain is a staple food that provides more food energy worldwide than any other type of crop.[2] Corn (maize), wheat, and rice – in all of their varieties – account for 87% of all grain production worldwide.[3][4][5] Most of the grain that is produced worldwide is fed to livestock.