phytochemical

Phytochemical derives by compounding the Ancient Greek word for plant (phytón, phyto) with chemical, as first used in English for plant chemistry and organic chemistry around 1850.{{cite web|url=https://www.oed.com/dictionary/phytochemical_adj|title=Phytochemical: adjective and noun |date=2025|publisher=Oxford English Dictionary|access-date=10 April 2025}}

Phytochemicals are chemicals produced by plants through primary or secondary metabolism.{{cite book|editor1-last=Harborne|editor1-first=Jeffrey B.|editor2-last=Baxter|editor2-first=Herbert|editor3-last=Moss|editor3-first=Gerard P.|title=Phytochemical dictionary a handbook of bioactive compounds from plants|date=1999|publisher=Taylor & Francis |location=London |isbn=9780203483756 |page=vii|edition=2nd |chapter-url=https://books.google.com/books?id=VCITWqQS_6MC&q=vast+array|chapter=General Introduction}} They generally have biological activity in the plant host and play a role in plant growth or defense against competitors, pathogens, or predators.{{cite journal|last1=Molyneux|first1=RJ|last2=Lee|first2=ST|last3=Gardner|first3=DR|last4=Panter|first4=KE|last5=James|first5=LF|title=Phytochemicals: the good, the bad and the ugly?|journal=Phytochemistry|date=2007|volume=68|issue=22–24|pages=2973–85|doi=10.1016/j.phytochem.2007.09.004|pmid=17950388|bibcode=2007PChem..68.2973M |url=https://naldc.nal.usda.gov/download/13290/PDF|access-date=2017-02-10|archive-date=2023-07-03|archive-url=https://web.archive.org/web/20230703140325/https://naldc.nal.usda.gov/download/13290/PDF|url-status=dead|url-access=subscription}} As components of plants, all individual phytochemicals make up the whole plant as it exists in nature.{{cite book|last1=Brielmann|first1=Harry L. |last2=Setzer|first2=William S. |last3= Kaufman|first3=Peter B. |last4= Kirakosyan|first4=Ara|last5=Cseke|first5=Leland J. |chapter=1 Phytochemicals The Chemical Components of Plants: 1.1 Introduction|chapter-url=https://books.google.com/books?id=wLxCEQAAQBAJ&pg=PP17|location=|editor-last1=|editor-first1= |editor-last2=|editor-first2=|title=

Natural Products from Plants|url=https://books.google.com/books?id=wLxCEQAAQBAJ&q=Phytochemicals|series=|language=|volume=|edition=2nd|publication-place=|publisher=CRC Press (Taylor & Francis)|publication-date=2016 |isbn=1040168523|issn=|access-date=9 April 2025|via=}}

Phytochemicals are generally regarded as research compounds rather than essential nutrients because proof of their possible health effects has not been established yet.{{cite web|last1=Heneman|first1=Karrie|last2=Zidenberg-Cherr|first2=Sheri|title=Publication 8313: Phytochemicals|url=http://anrcatalog.ucanr.edu/pdf/8313.pdf|publisher=University of California Cooperative Extension|date=2008}} Phytochemicals under research can be classified into major categories, such as carotenoids{{cite web| url=http://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals/carotenoids |title=Carotenoids |publisher=Micronutrient Information Center, Linus Pauling Institute, Oregon State University, Corvallis, Oregon|date=October 2023|access-date=9 April 2025}} and polyphenols, which include phenolic acids, flavonoids, stilbenes or lignans. Flavonoids can be further divided into groups based on their similar chemical structure, such as anthocyanins, flavones, flavanones, isoflavones, and flavanols. Flavanols are further classified as catechins, epicatechins, and proanthocyanidins. In total, between 50,000{{cite journal|last1=Afendi |first1=Farit Mochamad |last2=Okada |first2=Taketo |last3=Yamazaki |first3=Mami |last4=Hirai-Morita |first4=Aki |last5=Nakamura |first5=Yukiko |last6=Nakamura |first6=Kensuke |last7=Ikeda |first7=Shun |last8=Takahashi |first8=Hiroki |last9=Altaf-Ul-Amin |first9=Md. |last10=Darusman |first10=Latifah K. |last11=Saito |first11=Kazuki |last12=Kanaya |first12=Shigehiko |title=KNApSAcK Family Databases: Integrated Metabolite–Plant Species Databases for Multifaceted Plant Research |journal=Plant and Cell Physiology |date=February 2012 |volume=53 |issue=2 |pages=e1 |doi=10.1093/pcp/pcr165|pmid=22123792 |doi-access=free }} and 130,000{{cite journal|last1=Rutz |first1=Adriano |last2=Sorokina |first2=Maria |last3=Galgonek |first3=Jakub |last4=Mietchen |first4=Daniel |last5=Willighagen |first5=Egon |last6=Gaudry |first6=Arnaud |last7=Graham |first7=James G |last8=Stephan |first8=Ralf |last9=Page |first9=Roderic |last10=Vondrášek |first10=Jiří |last11=Steinbeck |first11=Christoph |last12=Pauli |first12=Guido F |last13=Wolfender |first13=Jean-Luc |last14=Bisson |first14=Jonathan |last15=Allard |first15=Pierre-Marie |title=The LOTUS initiative for open knowledge management in natural products research |journal=eLife |date=26 May 2022 |volume=11 |pages=e70780 |doi=10.7554/eLife.70780|pmid=35616633 |pmc=9135406 |doi-access=free }} phytochemicals have been discovered.

Phytochemists study phytochemicals by first extracting and isolating compounds from the origin plant, followed by defining their structure or testing in laboratory model systems, such as in vitro studies or in vivo studies using laboratory animals. Challenges in that field include isolating specific compounds and determining their structures, which are often complex, and identifying what specific phytochemical is primarily responsible for any given biological activity.

Further, upon consuming phytochemicals in a food entering the digestion process, the fate of individual phytochemicals in the body is unknown due to extensive metabolism in the gastrointestinal tract, producing smaller phytochemical metabolites with different biological properties from those of the parent compound, and with low bioavailability and rapid excretion. Other than for dietary fiber,{{cite web |url=http://lpi.oregonstate.edu/mic/other-nutrients/fiber |title=Fiber|publisher=Micronutrient Information Center, Linus Pauling Institute, Oregon State University, Corvallis, Oregon|date=2025|access-date=11 April 2025}} no non-nutrient phytochemical has sufficient scientific evidence in humans for an approved health claim.{{cite journal|author=EFSA Panel on Dietetic Products, Nutrition and Allergies |title=Scientific Opinion on the substantiation of health claims related to various food(s)/food constituent(s) and protection of cells from premature aging, antioxidant activity, antioxidant content and antioxidant properties, and protection of DNA, proteins and lipids from oxidative damage pursuant to Article 13(1) of Regulation (EC) No 1924/20061|journal= EFSA Journal|year= 2010|volume= 8|issue=2|page=1489|doi=10.2903/j.efsa.2010.1489|doi-access=free |url=https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2010.1489}}

File:Atropa belladonna Prague 2011 2.jpg

Without specific knowledge of their cellular actions or mechanisms, phytochemicals can be toxic or used in traditional medicine. For example, salicin, having anti-inflammatory and pain-relieving properties, was originally extracted from the bark of the white willow tree and later synthetically produced to become the common, over-the-counter drug, aspirin.{{Cite journal

| last1 = Sneader | first1 = W.

| title = The discovery of aspirin: A reappraisal

| journal = BMJ (Clinical Research Ed.)

| volume = 321

| issue = 7276

| pages = 1591–1594

| year = 2000

| pmid = 11124191

| pmc = 1119266

| doi=10.1136/bmj.321.7276.1591

}}{{cite web|url=http://www.cnn.com/2010/HEALTH/12/22/aspirin.history/|title=From a tree, a 'miracle' called aspirin|author=Landau E|publisher=CNN|date=22 Dec 2010|access-date=18 June 2014}} The tropane alkaloids of Atropa belladonna were used as poisons, and early humans made poisonous arrows from the plant.{{Cite book| last = Wink|first=Michael|editor1=Margaret F. Roberts|editor2=Michael Wink| year = 1998| title = Alkaloids : biochemistry, ecology, and medicinal applications| pages = 20|url=https://books.google.com/books?id=TMEGCAAAQBAJ&q=Alkaloids:+Biochemistry,+Ecology,+and+Medicinal+Applications|chapter=A Short History of Alkaloids|chapter-url = https://books.google.com/books?id=bMCzyrAtrvYC&q=hallucinogenic++Atropa+belladonna&pg=PA20| isbn = 978-0-306-45465-3| publisher = Plenum Press| location = New York}}{{Cite book| last = Timbrell | first = John| year = 2005| title = The poison paradox : chemicals as friends and foes| pages = [https://archive.org/details/poisonparadoxche0000timb/page/2 2]| url = https://archive.org/details/poisonparadoxche0000timb| url-access = registration | quote = poisons used by the wife of Claudius. | isbn = 978-0-19-280495-2| publisher = Oxford Univ. Pr.| location = Oxford}} Other uses include perfumes, such as the sesquiterpene santolols, from sandalwood.{{Cite book |last=Ellena |first=Jean-Claude |url=https://books.google.com/books?id=yrZNEAAAQBAJ |title=Atlas of Perfumed Botany |trans-title=Atlas de botanique parfumée|date=2022 |translator=Erik Butler |pages=12–15|orig-date=2020 Flammarion, Paris|publisher=MIT Press |location=Cambridge|isbn=978-0-262-04673-2 }}

The English yew tree was long known to be extremely and immediately toxic to animals that grazed on its leaves or children who ate its berries; however, in 1971, paclitaxel was isolated from it, subsequently becoming a cancer drug.

The biological activities for most phytochemicals are unknown or poorly understood, in isolation or as part of foods. Phytochemicals with established roles in the body are classified as essential nutrients.

The phytochemical category includes compounds recognized as essential nutrients, which are naturally contained in plants and are required for normal physiological functions, so must be obtained from the diet in humans.

Some phytochemicals are known phytotoxins that are toxic to humans;{{cite journal|last1=Iwasaki|first1=S|title=Natural organic compounds that affect to microtubule functions.|journal=Yakugaku Zasshi |date=April 1998|volume=118|issue=4|pages=112–26|doi=10.1248/yakushi1947.118.4_111|pmid=9564789|doi-access=free}}{{cite book|last1=Bjeldanes|first1=Leonard|last2=Shibamoto|first2=Takayuki|title=Introduction to Food Toxicology|date=2009|publisher=Elsevier|location=Burlington|isbn=9780080921532|page=124|edition=2nd|url=https://books.google.com/books?id=Lq4iw2UtDacC&pg=PA124}} for example aristolochic acid is carcinogenic at low doses.{{cite journal|last1=Shaw|first1=D|title=Toxicological risks of Chinese herbs.|journal=Planta Medica|date=December 2010|volume=76|issue=17|pages=2012–8|publisher=Georg Thieme Verlag KG|doi=10.1055/s-0030-1250533|pmid=21077025|doi-access=free|bibcode=2010PlMed..76.2012S}} Some phytochemicals are antinutrients that interfere with the absorption of nutrients.{{Cite journal|last1=Popova|first1=Aneta |last2= Mihaylova|first2=Dasha|date=July 2019|title=Antinutrients in Plant-based Foods: A Review - 1. INTRODUCTION|journal=The Open Biotechnology Journal|location=University of Food Technologies. Bulgaria|volume=13 |issue=1|pages=|doi=10.2174/1874070701913010068|via=T. Attwood, P. Campbell, H. Parish, A. Smith, F. Vella, J.Stirling Oxford Dictionary of Biochemistry and Molecular Biology. Oxford University Press, 2006. ISBN: 0-19-852917-1}} Others, such as some polyphenols and flavonoids, may be pro-oxidants in high ingested amounts.{{cite journal|pmid=17141749|year=2007|last1=Halliwell|first1=B|title=Dietary polyphenols: Good, bad, or indifferent for your health?|journal=Cardiovascular Research|volume=73|issue=2|pages=341–7|doi=10.1016/j.cardiores.2006.10.004|doi-access=free}}

Non-digestible dietary fibers from plant foods, often considered as a phytochemical, are generally regarded as a nutrient group having approved health claims for reducing the risk of some types of cancer{{cite web|url=http://www.ecfr.gov/cgi-bin/text-idx?SID=c7e427855f12554dbc292b4c8a7545a0&mc=true&node=pt21.2.101&rgn=div5#se21.2.101_176 |website=eCFR |title=Health claims: fiber-containing grain products, fruits, and vegetables and cancer; Title 21: Food and Drugs, Subpart E, 101.76|publisher=U.S. Food and Drug Administration|date=5 January 2017|access-date=8 January 2017}} and coronary heart disease.{{cite web|url=http://www.ecfr.gov/cgi-bin/text-idx?SID=c7e427855f12554dbc292b4c8a7545a0&mc=true&node=pt21.2.101&rgn=div5#se21.2.101_181 |website=eCFR |title=Health claims: Soluble fiber from certain foods and risk of coronary heart disease (CHD); Title 21: Food and Drugs, Subpart E, 101.81|publisher=U.S. Food and Drug Administration|date=5 January 2017|access-date=8 January 2017}}

Phytochemical dietary supplements are neither recommended by health authorities for improving health{{cite web|url=http://www.cancer.org/healthy/eathealthygetactive/acsguidelinesonnutritionphysicalactivityforcancerprevention/acs-guidelines-on-nutrition-and-physical-activity-for-cancer-prevention-common-questions|title=Common questions about diet and cancer|date=5 February 2016|publisher=American Cancer Society|access-date=8 January 2017 |url-status=dead |archive-url= https://web.archive.org/web/20161227093224/http://www.cancer.org/healthy/eathealthygetactive/acsguidelinesonnutritionphysicalactivityforcancerprevention/acs-guidelines-on-nutrition-and-physical-activity-for-cancer-prevention-common-questions |archive-date= Dec 27, 2016 }} nor are they approved by regulatory agencies for health claims on product labels.{{cite web|url=https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-101/subpart-D|title=Code of Federal Regulations, Title 21, Part 101, Food Labeleing, Subpart D, Specific Requirements for Nutrient Content Claims, Section 101.54|publisher= US Food and Drug Administration|date=29 July 2016|access-date=11 April 2025}}

While health authorities encourage consumers to eat diets rich in fruit, vegetables, whole grains, legumes, and nuts to improve and maintain health, evidence that such effects result from specific, non-nutrient phytochemicals is limited or absent. For example, systematic reviews and/or meta-analyses indicate weak or no evidence for phytochemicals from plant food consumption having an effect on breast, lung, or bladder cancers.{{cite journal|pmid=22706630|year=2012|last1=Aune|first1=D|title=Fruits, vegetables and breast cancer risk: A systematic review and meta-analysis of prospective studies|journal=Breast Cancer Research and Treatment|volume=134|issue=2|pages=479–93|last2=Chan|first2=D. S.|last3=Vieira|first3=A. R.|last4=Rosenblatt|first4=D. A.|last5=Vieira|first5=R|last6=Greenwood|first6=D. C.|last7=Norat|first7=T|doi=10.1007/s10549-012-2118-1|s2cid=6984786|url=http://eprints.whiterose.ac.uk/75579/15/Combine.pdf}}{{cite journal|pmid=14601062|year=2003|last1=Smith-Warner|first1=S. A.|title=Fruits, vegetables and lung cancer: A pooled analysis of cohort studies|journal=International Journal of Cancer|volume=107|issue=6|pages=1001–11|last2=Spiegelman|first2=D|last3=Yaun|first3=S. S.|last4=Albanes|first4=D|last5=Beeson|first5=W. L.|last6=Van Den Brandt|first6=P. A.|last7=Feskanich|first7=D|last8=Folsom|first8=A. R.|last9=Fraser|first9=G. E.|last10=Freudenheim|first10=J. L.|last11=Giovannucci|first11=E|last12=Goldbohm|first12=R. A.|last13=Graham|first13=S|last14=Kushi|first14=L. H.|last15=Miller|first15=A. B.|last16=Pietinen|first16=P|last17=Rohan|first17=T. E.|last18=Speizer|first18=F. E.|last19=Willett|first19=W. C.|last20=Hunter|first20=D. J.|doi=10.1002/ijc.11490|s2cid=28381529|url=https://cris.maastrichtuniversity.nl/portal/en/publications/fruits-vegetables-and-lung-cancer-a-pooled-analysis-of-cohort-studies(e5a7f16c-9f94-461e-9454-f35522b553f5).html|doi-access=free}} Further, in the United States, regulations exist to limit the language on product labels for how plant food consumption may affect cancers, excluding mention of any phytochemical except for those with established health benefits against cancer, such as dietary fiber, vitamin A, and vitamin C.{{cite web|url=http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=1&SID=4bf49f997b04dcacdfbd637db9aa5839&ty=HTML&h=L&mc=true&n=pt21.2.101&r=PART#se21.2.101_178|title=Electronic Code of Federal Regulations, Title 21, Chapter I, Subchapter B, Part 101.78. Health claims: fruits and vegetables and cancer|publisher=US Government Printing Office|date=9 February 2017|access-date=12 February 2017}}

Phytochemicals, such as polyphenols, have been specifically discouraged from food labeling in Europe and the United States because there is no evidence for a cause-and-effect relationship between dietary polyphenols and inhibition or prevention of any disease.{{citation |title= New Roles for Polyphenols. A 3-Part Report on Current Regulations & the State of Science |author= Gross P|date=1 March 2009 |publisher= Nutraceuticals World (republished by The Free Library) |url= https://www.thefreelibrary.com/New+roles+for+polyphenols%3a+a+3-part+report+on+current+regulations+%26...-a0196242906|access-date=12 February 2017|via=www.nutraceuticalsworld.com/new-roles-for-polyphenols/}}

Among carotenoids such as the tomato phytochemical, lycopene, the US Food and Drug Administration found insufficient evidence for its effects on any of several cancer types, resulting in limited language for how products containing lycopene can be described on labels.{{cite web|url=https://www.fda.gov/Food/IngredientsPackagingLabeling/LabelingNutrition/ucm072760.htm|archive-url=https://web.archive.org/web/20131002010733/http://www.fda.gov/Food/IngredientsPackagingLabeling/LabelingNutrition/ucm072760.htm|url-status=dead|archive-date=2 October 2013|title=Qualified Health Claims: Letter Regarding "Tomatoes and Prostate, Ovarian, Gastric and Pancreatic Cancers (American Longevity Petition)" (Docket No. 2004Q-0201)|publisher=Office of Nutritional Products, Labeling and Dietary Supplements, Center for Food Safety and Applied Nutrition, US Food and Drug Administration |author=Schneeman BO|date=9 July 2015|access-date=12 February 2017}}

Phytochemicals in freshly harvested plant foods may be degraded by processing techniques, including cooking.{{Cite journal

| pmid = 24227349

| year = 2014

| last1 = Palermo

| first1 = M

| title = The effect of cooking on the phytochemical content of vegetables

| journal = Journal of the Science of Food and Agriculture

| volume = 94

| issue = 6

| pages = 1057–70

| last2 = Pellegrini

| first2 = N

| last3 = Fogliano

| first3 = V

| doi = 10.1002/jsfa.6478

| bibcode = 2014JSFA...94.1057P

| hdl = 11381/2677278

| hdl-access = free

}} The main cause of phytochemical loss from cooking is thermal decomposition.

A converse exists in the case of carotenoids, such as lycopene present in tomatoes, which may remain stable or increase in content from cooking due to liberation from cellular membranes in the cooked food.{{cite journal |pmid=11982434 |year=2002 |last1=Dewanto |first1=V |last2=Wu |last3=Adom |last4=Liu |title=Thermal processing enhances the nutritional value of tomatoes by increasing total antioxidant activity |volume=50 |issue=10 |pages=3010–4 |journal=Journal of Agricultural and Food Chemistry |doi=10.1021/jf0115589 |first2=X |first3=KK |first4=RH|bibcode=2002JAFC...50.3010D }} Food processing techniques like mechanical processing can also free carotenoids and other phytochemicals from the food matrix, increasing dietary intake.{{Cite journal

| pmid = 17374686

| year = 2007

| last1 = Hotz

| first1 = C

| title = Traditional food-processing and preparation practices to enhance the bioavailability of micronutrients in plant-based diets

| journal = The Journal of Nutrition

| volume = 137

| issue = 4

| pages = 1097–100

| last2 = Gibson

| first2 = R. S.

| doi = 10.1093/jn/137.4.1097

| doi-access = free

}}

In some cases, processing of food is necessary to remove phytotoxins or antinutrients; for example societies that use cassava as a staple have traditional practices that involve some processing (soaking, cooking, fermentation), which are necessary to avoid illness from cyanogenic glycosides present in unprocessed cassava.{{cite book|author= O L. Oke|title=Roots, tubers, plantains and bananas in human nutrition|date=31 December 1990|publisher=Food & Agriculture Organization of the United Nations |location=Rome|url=http://www.fao.org/docrep/t0207e/T0207E00.htm#Contents|isbn= 9251028621|chapter-url=http://www.fao.org/docrep/t0207e/T0207E08.htm#Cassava%20toxicity|chapter=Chapter 7: Toxic substances and antinutritional factors}}

• Allelopathy
• List of antioxidants in food
• List of phytochemicals in food
• Nutrition
• Secondary metabolites

{{Reflist}}

• Higdon, J. An Evidence – Based Approach to Dietary Phytochemicals. 2007. Thieme. {{ISBN|978-1-58890-408-9}}.
• Rosa, L.A. de la / Alvarez-Parrilla, E. / González-Aguilar, G.A. (eds.) Fruit and Vegetable Phytochemicals: Chemistry, Nutritional Value and Stability. 2010. Wiley-Blackwell. {{ISBN|978-0-8138-0320-3}}.

• {{Commons category-inline|Phytochemicals}}
• [https://phytochem.nal.usda.gov/phytochem/search Dr. Duke's Phytochemical and Ethnobotanical Databases] – United States Department of Agriculture

{{Phytochemical}}

Category:Dietary antioxidants

Category:Nutrients

Category:Nutrition

Category:Polyphenols

Category:Carotenoids