In 2005, the population of the United States spent $496 billion on out-of-home dining. Expenditures by type of out-of-home dining were as follows: 40% in full-service restaurants, 37.2% in limited service restaurants (fast food), 6.6% in schools or colleges, 5.4% in bars and vending machines, 4.7% in hotels and motels, 4.0% in recreational places, and 2.2% in others, which includes military bases.[105][better source needed][relevant? – discuss]
Fertilizing and the use of pesticides in conventional farming has caused, and is causing, enormous damage worldwide to local ecosystems, biodiversity, groundwater and drinking water supplies, and sometimes farmer health and fertility. These environmental, economic and health issues are intended to be minimized or avoided in organic farming. From a consumers perspective, there is not sufficient evidence in scientific and medical literature to support claims that organic food is safer or healthier to eat than conventionally grown food. While there may be some differences in the nutrient and antinutrient contents of organically- and conventionally-produced food, the variable nature of food production and handling makes it difficult to generalize results.[47][48][49][50][51] Claims that organic food tastes better are generally not supported by tests.[48][52]
Adulteration is a legal term meaning that a food product fails to meet the legal standards. One form of adulteration is an addition of another substance to a food item in order to increase the quantity of the food item in raw form or prepared form, which may result in the loss of actual quality of food item. These substances may be either available food items or non-food items. Among meat and meat products some of the items used to adulterate are water or ice, carcasses, or carcasses of animals other than the animal meant to be consumed.[13]

There are very many methods of cooking, most of which have been known since antiquity. These include baking, roasting, frying, grilling, barbecuing, smoking, boiling, steaming and braising. A more recent innovation is microwaving. Various methods use differing levels of heat and moisture and vary in cooking time. The method chosen greatly affects the end result because some foods are more appropriate to some methods than others. Some major hot cooking techniques include:

Communication between the Old World and the New World in the Columbian Exchange influenced the history of cooking. The movement of foods across the Atlantic, from the New World, such as potatoes, tomatoes, maize, beans, bell pepper, chili pepper, vanilla, pumpkin, cassava, avocado, peanut, pecan, cashew, pineapple, blueberry, sunflower, chocolate, gourds, and squash, had a profound effect on Old World cooking. The movement of foods across the Atlantic, from the Old World, such as cattle, sheep, pigs, wheat, oats, barley, rice, apples, pears, peas, chickpeas, green beans, mustard, and carrots, similarly changed New World cooking.[11]
Kosher foods are those that conform to the Jewish dietary regulations of kashrut (dietary law), primarily derived from Leviticus and Deuteronomy. Food that may be consumed according to halakha (law) is termed kosher (/ˈkoʊʃər/) in English, from the Ashkenazi pronunciation of the Hebrew term kashér (כָּשֵׁר), meaning "fit" (in this context, fit for consumption). Food that is not in accordance with law is called treif (/treɪf/; Yiddish: טרײף‎, derived from Hebrew: טְרֵפָה‎ trāfáh) meaning "torn."

Fruits are the ripened ovaries of plants, including the seeds within. Many plants and animals have coevolved such that the fruits of the former are an attractive food source to the latter, because animals that eat the fruits may excrete the seeds some distance away. Fruits, therefore, make up a significant part of the diets of most cultures. Some botanical fruits, such as tomatoes, pumpkins, and eggplants, are eaten as vegetables.[10] (For more information, see list of fruits.)