Editing Food (section)

==Definition and classification==
Food is any substance consumed to provide [[Nutrient|nutritional]] support and energy to an [[organism]].<ref>{{Cite web |title=Food definition and meaning |url=https://www.collinsdictionary.com/dictionary/english/food |url-status=live |archive-url=https://web.archive.org/web/20210501034215/https://www.collinsdictionary.com/dictionary/english/food |archive-date=1 May 2021 |access-date=21 August 2021 |website=Collins English Dictionary |language=en}}</ref><ref name=":6" /> It can be raw, processed, or formulated and is consumed orally by animals for growth, health, or pleasure. Food is mainly composed of water, [[lipid]]s, [[protein]]s, and [[carbohydrate]]s. Minerals (e.g., salts) and organic substances (e.g., [[vitamin]]s) can also be found in food.<ref>{{Cite journal |last1=Rahman |first1=M. Shafiur |last2=McCarthy |first2=Owen J. |date=July 1999 |title=A classification of food properties |journal=International Journal of Food Properties |language=en |volume=2 |issue=2 |pages=93–99 |doi=10.1080/10942919909524593 |issn=1094-2912|doi-access=free }}</ref> Plants, [[algae]], and some microorganisms use [[photosynthesis]] to make some of their own nutrients.<ref>{{Cite web |date=12 April 2017 |title=What is Photosynthesis |url=https://ssec.si.edu/stemvisions-blog/what-photosynthesis |url-status=live |archive-url=https://web.archive.org/web/20211203164642/https://ssec.si.edu/stemvisions-blog/what-photosynthesis |archive-date=3 December 2021 |access-date=3 December 2021 |website=Smithsonian Science Education Center |language=en}}</ref> Water is found in many foods and has been defined as food by itself.<ref>{{Cite web |date=11 February 2020 |title=CPG Sec 555.875 Water in Food Products (Ingredient or Adulterant) |url=https://www.fda.gov/regulatory-information/search-fda-guidance-documents/cpg-sec-555875-water-food-products-ingredient-or-adulterant |url-status=live |archive-url=https://web.archive.org/web/20211203164643/https://www.fda.gov/regulatory-information/search-fda-guidance-documents/cpg-sec-555875-water-food-products-ingredient-or-adulterant |archive-date=3 December 2021 |access-date=3 December 2021 |website=U.S. Food and Drug Administration |language=en}}</ref> Water and [[Dietary fiber|fiber]] have low energy densities, or [[calorie]]s, while fat is the most energy-dense component.<ref name=":6">{{Cite web |title=Low-Energy-Dense Foods and Weight Management: Cutting Calories While Controlling Hunger |url=https://www.cdc.gov/nccdphp/dnpa/nutrition/pdf/r2p_energy_density.pdf |url-status=live |archive-url=https://web.archive.org/web/20211118001657/https://www.cdc.gov/nccdphp/dnpa/nutrition/pdf/r2p_energy_density.pdf |archive-date=18 November 2021 |access-date=3 December 2021 |website=[[Centers for Disease Control and Prevention]]}}</ref> Some inorganic (non-food) elements are also essential for plant and animal functioning.<ref>{{Cite journal |last1=Zoroddu |first1=Maria Antonietta |last2=Aaseth |first2=Jan |last3=Crisponi |first3=Guido |last4=Medici |first4=Serenella |last5=Peana |first5=Massimiliano |last6=Nurchi |first6=Valeria Marina |date=1 June 2019 |title=The essential metals for humans: a brief overview |url=https://www.sciencedirect.com/science/article/pii/S0162013418306846 |url-status=live |journal=Journal of Inorganic Biochemistry |language=en |volume=195 |pages=120–129 |doi=10.1016/j.jinorgbio.2019.03.013 |issn=0162-0134 |pmid=30939379 |archive-url=https://web.archive.org/web/20220411181017/https://www.sciencedirect.com/science/article/pii/S0162013418306846 |archive-date=11 April 2022 |access-date=11 April 2022 |s2cid=92997696}}</ref>

Human food can be classified in various ways, either by related content or by how it is processed.<ref>{{Cite journal |last1=Sadler |first1=Christina R. |last2=Grassby |first2=Terri |last3=Hart |first3=Kathryn |last4=Raats |first4=Monique |last5=Sokolović |first5=Milka |last6=Timotijevic |first6=Lada |date=1 June 2021 |title=Processed food classification: Conceptualisation and challenges |journal=Trends in Food Science & Technology |language=en |volume=112 |pages=149–162 |doi=10.1016/j.tifs.2021.02.059 |issn=0924-2244 |doi-access=free |s2cid=233647428}}</ref> The number and composition of [[food group]]s can vary. Most systems include four basic groups that describe their origin and relative nutritional function: Vegetables and Fruit, Cereals and Bread, Dairy, and Meat.<ref>{{Cite book |last=Nestle |first=Marion |title=Food Politics: How the Food Industry Influences Nutrition and Health |publisher=University of California Press |year=2013 |isbn=978-0-520-27596-6 |pages=36–37 |author-link=Marion Nestle |orig-date=2002}}</ref> Studies that look into diet quality group food into whole grains/cereals, refined grains/cereals, vegetables, fruits, nuts, legumes, eggs, dairy products, fish, red meat, processed meat, and sugar-sweetened beverages.<ref>{{Cite journal |last1=Schwingshackl |first1=Lukas |last2=Schwedhelm |first2=Carolina |last3=Hoffmann |first3=Georg |last4=Lampousi |first4=Anna-Maria |last5=Knüppel |first5=Sven |last6=Iqbal |first6=Khalid |last7=Bechthold |first7=Angela |last8=Schlesinger |first8=Sabrina |last9=Boeing |first9=Heiner |year=2017 |title=Food groups and risk of all-cause mortality: a systematic review and meta-analysis of prospective studies |journal=The American Journal of Clinical Nutrition |volume=105 |issue=6 |pages=1462–1473 |doi=10.3945/ajcn.117.153148 |issn=0002-9165 |pmid=28446499 |doi-access=free |s2cid=22494319}}</ref><ref>{{Cite journal |last1=Schwingshackl |first1=Lukas |last2=Schwedhelm |first2=Carolina |last3=Hoffmann |first3=Georg |last4=Knüppel |first4=Sven |last5=Preterre |first5=Anne Laure |last6=Iqbal |first6=Khalid |last7=Bechthold |first7=Angela |last8=Henauw |first8=Stefaan De |last9=Michels |first9=Nathalie |last10=Devleesschauwer |first10=Brecht |last11=Boeing |first11=Heiner |year=2018 |title=Food groups and risk of colorectal cancer |journal=International Journal of Cancer |language=en |volume=142 |issue=9 |pages=1748–1758 |doi=10.1002/ijc.31198 |issn=1097-0215 |pmid=29210053 |doi-access=free}}</ref><ref>{{Cite journal |last1=Schwingshackl |first1=Lukas |last2=Hoffmann |first2=Georg |last3=Lampousi |first3=Anna-Maria |last4=Knüppel |first4=Sven |last5=Iqbal |first5=Khalid |last6=Schwedhelm |first6=Carolina |last7=Bechthold |first7=Angela |last8=Schlesinger |first8=Sabrina |last9=Boeing |first9=Heiner |date=May 2017 |title=Food groups and risk of type 2 diabetes mellitus: a systematic review and meta-analysis of prospective studies |journal=European Journal of Epidemiology |language=en |volume=32 |issue=5 |pages=363–375 |doi=10.1007/s10654-017-0246-y |issn=0393-2990 |pmc=5506108 |pmid=28397016}}</ref> The [[Food and Agriculture Organization]] and [[World Health Organization]] use a system with nineteen food classifications: cereals, roots, pulses and nuts, milk, eggs, fish and shellfish, meat, insects, vegetables, fruits, fats and oils, sweets and sugars, spices and condiments, beverages, foods for nutritional uses, food additives, composite dishes and savory snacks.<ref>{{Cite web |title=Food groups and sub-groups |url=http://www.fao.org/gift-individual-food-consumption/methodology/food-groups-and-sub-groups/en/ |url-status=live |archive-url=https://web.archive.org/web/20210829000613/http://www.fao.org/gift-individual-food-consumption/methodology/food-groups-and-sub-groups/en/ |archive-date=29 August 2021 |access-date=29 August 2021 |website=FAO}}</ref>