The grapefruit (Citrus × paradisi) is a subtropical citrus tree known for its relatively large, sour to semi-sweet, somewhat bitter fruit.[1] The interior flesh is segmented and varies in color from pale yellow to dark pink/red.

Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Sapindales
Family: Rutaceae
Genus: Citrus
C. × paradisi
Binomial name
Citrus × paradisi

Grapefruit is a citrus hybrid that originated in Barbados in the 18th century. It is an accidental cross between the sweet orange (C. × sinensis) and the pomelo or shaddock (C. maxima), both of which were introduced from Asia in the 17th century.[2] It has also been called the forbidden fruit.[1] In the past it was referred to as the pomelo,[3] but that term is now mostly used as the common name for Citrus maxima.[4]


Grapefruit growing in the grape-like clusters from which their name may derive

The evergreen grapefruit trees usually grow to around 5–6 m (16–20 ft) tall, although they may reach 13–15 m (43–49 ft).[1] The leaves are long (up to 15 cm (5.9 in)), thin, glossy, and dark green. They produce 5 cm (2 in) white four or five petaled flowers. The fruit is yellow-orange skinned and generally an oblate spheroid in shape; it ranges in diameter from 10 to 15 cm (3.9 to 5.9 in). Its flesh is segmented and acidic, varying in color depending on the cultivars, which include white, pink, and red pulps of varying sweetness (generally, the redder varieties are the sweetest).[1] The 1929 U.S. 'Ruby Red'[1] (of the 'Redblush' variety) was the first grapefruit patent.[5] Grapefruits are one of the most common hosts for fruit flies such as A. suspensa, which lay their eggs in overripe or spoiled grapefruits.[6] The larvae of these flies then consume the fruit to gain nutrients until they can proceed into the pupae stage. This parasitism has led to millions in economic costs for nations in Central America and southern North America.[7]



The varieties of Texas and Florida grapefruit include: 'Duncan', 'Flame', 'Henderson', 'Hudson', 'Marsh', 'Oro Blanco', 'Pink', 'Pummelo HB', 'Ray', 'Rio Star', 'Ruby Red', 'Star Ruby', 'Thompson', 'Triumph', 'Walters', 'White Marsh'.[8]

"Red" grapefruit

The 1929 'Ruby Red' (or 'Redblush') patent was associated with real commercial success, which came after the discovery of a red grapefruit growing on a pink variety.[1] It was a limb sport of a 'Thompson' grapefruit selected by A.E. Henninger. The 'Thompson' was a limb sport from a 'Marsh' grapefruit selected in 1913.[citation needed] The Texas Legislature designated this grapefruit variety the official "State Fruit of Texas" in 1993.[9]

Using radiation to trigger mutations, new varieties were developed to retain the red tones that typically faded to pink.[10] The 'Rio Red' variety is a 1984 registered Texas grapefruit with registered trademarks Rio Star and Ruby-Sweet, also sometimes promoted as Reddest and Texas Choice. The 'Rio Red' is a mutation-bred variety that was developed by treatment of bud sticks with thermal neutrons. Its improved attributes of mutant variety are fruit and juice color, deeper red, and wide adaptation.[11]

The 'Star Ruby' is the darkest of the red varieties.[1] Developed from an irradiated 'Hudson' grapefruit ('Hudson' being a limb sport of 'Foster', itself a limb sport of the 'Walters'),[12] it has found limited commercial success because it is more difficult to grow than other varieties.[13][14]


Grapefruit, raw, white, all areas
Nutritional value per 100 g (3.5 oz)
Energy138 kJ (33 kcal)
8.41 g
Sugars7.31 g
Dietary fiber1.1 g
0.10 g
0.8 g
Thiamine (B1)
0.037 mg
Riboflavin (B2)
0.020 mg
Niacin (B3)
0.269 mg
Pantothenic acid (B5)
0.283 mg
Vitamin B6
0.043 mg
Folate (B9)
10 μg
7.7 mg
Vitamin C
33.3 mg
Vitamin E
0.13 mg
12 mg
0.06 mg
9 mg
0.013 mg
8 mg
148 mg
0.07 mg
Other constituentsQuantity
Water90.48 g

Percentages estimated using US recommendations for adults,[15] except for potassium, which is estimated based on expert recommendation from the National Academies.[16]

Raw white grapefruit is 90% water, 8% carbohydrates, 1% protein, and contains negligible fat (table). In a reference amount of 100 grams (3.5 oz), raw grapefruit provides 33 kilocalories and is a rich source of vitamin C (40% of the Daily Value), with no other micronutrients in significant content. A grapefruit supplies about 10% of your daily potassium needs, along with 8% of your requirements for thiamine and folate.[17] Grapefruit juice contains about half the citric acid of lime or lemon juice, and about 93% more citric acid than orange juice.[18]

Caramelized grapefruit served at a diner





In Costa Rica, especially in Atenas, grapefruit are often cooked to remove their sourness, rendering them as sweets; they are also stuffed with dulce de leche, resulting in a dessert called toronja rellena (stuffed grapefruit).[19] In Haiti, grapefruit is used primarily for its juice (jus de Chadèque), but also is used to make jam (confiture de Chadèque).[20][21]

Grapefruit varieties are differentiated by the flesh color of fruit they produce. Common varieties are yellow and pink pulp colors. Flavors range from highly acidic and somewhat sour to sweet and tart, resulting from composition of sugars (mainly sucrose), organic acids (mainly citric acid), and monoterpenes and sesquiterpenes providing aromas.[22] Grapefruit mercaptan, a sulfur-containing terpene, is one of the aroma compounds influencing taste and odor of grapefruit, compared with other citrus fruits.[23]

Drug interactions


Grapefruit and grapefruit juice have been found to interact with numerous drugs, possibly resulting in adverse effects.[24][25] Possible effects include abnormal heart rhythms, bleeding inside the stomach, low blood pressure, difficulty breathing, and dizziness, among others.[25]

One interaction occurs from grapefruit furanocoumarins, such as bergamottin and 6',7'-dihydroxybergamottin, which occur in both flesh and peel. Furanocoumarins inhibit the CYP3A4 enzyme (among others from the P450 enzyme family responsible for metabolizing 90% of drugs). The action of the CYP3A4 enzyme itself is to metabolize many medications.[25] If the drug's breakdown for removal is lessened, then the level of the drug in the blood may become and remain high, leading to adverse effects.[24][25] On the other hand, some drugs must be metabolized to become active, and inhibiting CYP3A4 may lead to reduced drug effects.[24][25]

The other effect is that grapefruit compounds may inhibit the absorption of drugs in the intestine. If the drug is not absorbed, then not enough of it is in the blood to have a therapeutic effect. Each affected drug has either a specific increase of effect or decrease.[26]

One whole grapefruit or a glass of 200 ml (7 US fl oz) of grapefruit juice may cause drug overdose toxicity.[24] Typically, drugs that are incompatible with grapefruit are so labeled on the container or package insert.[24][25]

Grapefruit production – 2022
Country Millions of tonnes
  China 5.2
  Vietnam 1.1
  Mexico 0.5
  South Africa 0.4
  United States 0.3
World 9.8
Source: FAOSTAT of the United Nations[27]



In 2022, world production of grapefruits (combined with pomelos) was 9.8 million tonnes, led by China with 53% of the world total with Vietnam as a secondary producer.



Grapefruit originated as a natural hybrid.[28] One ancestor of the grapefruit was the Jamaican sweet orange (Citrus sinensis), itself an ancient hybrid of Asian origin; the other was the Indonesian pomelo (C. maxima).[1] Both C. sinensis and C. maxima were present in the West Indies by 1692. One story of the fruit's origin is that a certain "Captain Shaddock"[1] brought pomelo seeds to Jamaica and bred the first fruit, which were then called shaddocks.[29] This apparently referred to a captain who traded in the West Indies in the 17th century.[30] The grapefruit then probably originated as a naturally occurring hybrid between the two plants some time after they had been introduced there.[1][2]

A hybrid fruit, called forbidden fruit, was first documented in 1750 (along with 14 other citrus fruits including the guiney orange) by a Welshman, Rev. Griffith Hughes, who described specimens from Barbados in The Natural History of Barbados.[1][31][32] However, Hughes's forbidden fruit may have been a plant distinct from grapefruit although still closely related to it.[33]

Kimball Chase Atwood

In 1814, naturalist John Lunan published the term grapefruit to describe a similar Jamaican citrus plant.[29] Lunan reported that the name was due to its similarity in taste to the grape (Vitis vinifera).[34] An alternative explanation offered by Tussac (1824) is that this name may allude to clusters of the fruit on the tree, which often appear similar to bunches of grapes.[35] After this, authors of the period used both terms forbidden fruit and grapefruit as synonyms.[citation needed]

In 1830, the Jamaican version of the plant was given the botanical name Citrus paradisi by botanist James Macfadyen.[36] Macfadyen identified two varieties – one called forbidden fruit, the other called Barbadoes Grape Fruit. Macfadyen distinguished between the two plants by fruit shape with the Barbados grapefruit being piriform (pear shaped) while the forbidden fruit was "maliformis." Macfadyen's and Hughes's description differ, so it is not clear that the two reports are describing the same plant. Kumamoto et al. (1987) suggest that Hughes's golden orange was actually a grapefruit while his forbidden fruit was a different plant that had since became extinct and frequently confused with grapefruits. Later, Kim (1990) found a different citrus called forbidden fruit or shaddette in Saint Lucia that is closely related to grapefruits and may be the plant described by Hughes and Macfadyen.[citation needed]

The name grape-fruit was used more and more during the 19th century to refer to pomelos, to the consternation of some.[37] It was brought to Florida by Count Odet Philippe in 1823, in what is now known as Safety Harbor.[1] Further crosses have produced the tangelo (1905), the Minneola tangelo (1931), and the oroblanco (1984). Its true origins were not determined until the 1940s. This led to the official name being altered to Citrus × paradisi, the × identifying its hybrid origin.[38][39] An early pioneer in the American citrus industry was Kimball C. Atwood, a wealthy entrepreneur who founded the Atwood Grapefruit Company in the late 19th century. The Atwood Grove became the largest grapefruit grove in the world, with a yearly output of 80,000 boxes of fruit.[40] There, pink grapefruit was first discovered in 1906.[1]


Grapefruit is a pomelo backcross, a hybrid of pomelo and sweet orange, which is in turn a pomelo × mandarin hybrid.

The grapefruit is a parent to many hybrids:

  • A tangelo is any hybrid of a tangerine and either a pomelo or a grapefruit
  • The 'Oroblanco' and 'Melogold' grapefruits are hybrids between pomelo (C. maxima) and the grapefruit
  • The 'Triumph' grapefruit is thought to be a hybrid between a grapefruit and one of either an orange, a mandarin orange, or a pomelo

Related citrus fruits include:

See also



  1. ^ a b c d e f g h i j k l m Morton, Julia Frances (1987). "Grapefruit, Citrus paradisi, In: Fruits of Warm Climates". NewCROP, New Crop Resource Online Program, Center for New Crops and Plant Products, Department of Horticulture and Landscape Architecture, Purdue University. pp. 152–158. ISBN 978-0-9610184-1-2. OCLC 16947184. Archived from the original on 2000-10-06. Retrieved 2003-03-28.
  2. ^ a b Carrington, Sean; Fraser, Henry C. (2003). "Grapefruit". A~Z of Barbados Heritage. Macmillan Caribbean. pp. 90–91. ISBN 978-0-333-92068-8. One of many citrus species grown in Barbados. This fruit is believed to have originated in Barbados as a natural cross between sweet orange (C. sinesis) and pomelo (C. grandis), both of which originated in Asia and were introduced by Europeans in the 17th century. The grapefruit first appeared as an illustration entitled 'The Forbidden Fruit Tree' in The Natural History of Barbados (1750) by Rev. Griffith Hughes. This accords with the scientific name, which literally is 'citrus of paradise'. The fruit seems to have been fairly commonly available around that time, since George Washington in his Barbados Journal (1750-1751) mentions 'the Forbidden Fruit' as one of the local fruit available at a dinner party he attended. The plant was later described in the 1837 Flora of Jamaica as the Barbados Grapefruit. The historical arguments and experimental work on leaf enzymes and oils from possible parents all support a Barbadian origin for the fruit.
  3. ^ The American Heritage Dictionary of the English Language (1973) defines "pomelo" simply as "The grapefruit".
  4. ^ Li, Xiaomeng; Xie R.; Lu Z.; Zhou Z. (July 2010). "The Origin of Cultivated Citrus as Inferred from Internal Transcribed Spacer and Chloroplast DNA Sequence and Amplified Fragment Length Polymorphism Fingerprints". Journal of the American Society for Horticultural Science. 135 (4): 341. doi:10.21273/JASHS.135.4.341.
  5. ^ Texas grapefruit history Archived 2010-11-28 at the Wayback Machine, TexaSweet. Retrieved 2 July 2008.
  6. ^ van Whervin, L. Walter (March 1974). "Some Fruitflies (Tephritidae) in Jamaica". PANS Pest Articles & News Summaries. 20 (1): 11–19. doi:10.1080/09670877409412331. ISSN 0030-7793.
  7. ^ McPheron, BA, Steck GJ (1996). Fruit fly pests: a world assessment of their biology and management. St. Lucie, Florida: St. Lucie Press. ISBN 1574440144. OCLC 34343237.
  8. ^ "Go Florida Grapefruit". Go Florida Grapefruit. Archived from the original on 2011-09-10. Retrieved 2011-12-17.
  9. ^ Hatch, Rosie (Ed.) (2022). Texas Almanac 2022-2023. Austin, Texas: Texas State Historical Association. p. 21. ISBN 9781625110664.
  10. ^ William J Broad (28 August 2007). "Useful Mutants, Bred With Radiation". The New York Times. Archived from the original on 1 February 2017. Retrieved 22 February 2017.
  11. ^ "MVD". Archived from the original on 2014-03-19. Retrieved 2017-03-30.
  12. ^ Ahloowalia, B.S.; Maluszynski, M.; Nichterlein, K. (2004). "Global impact of mutation-derived varieties". Euphytica. 135 (2): 187–204. doi:10.1023/B:EUPH.0000014914.85465.4f. S2CID 34494057.
  13. ^ Sauls, Julian W. (1998). "Home fruit Production-Grapefruit". Archived from the original on 2013-07-30. Retrieved 2013-07-22.
  14. ^ Citrus Variety Collection. "Star Ruby grapefruit". Archived from the original on 2013-06-19. Retrieved 2013-07-22.
  15. ^ United States Food and Drug Administration (2024). "Daily Value on the Nutrition and Supplement Facts Labels". FDA. Archived from the original on 2024-03-27. Retrieved 2024-03-28.
  16. ^ National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee to Review the Dietary Reference Intakes for Sodium and Potassium (2019). Oria, Maria; Harrison, Meghan; Stallings, Virginia A. (eds.). Dietary Reference Intakes for Sodium and Potassium. The National Academies Collection: Reports funded by National Institutes of Health. Washington, DC: National Academies Press (US). ISBN 978-0-309-48834-1. PMID 30844154. Archived from the original on 2024-05-09. Retrieved 2024-06-21.
  17. ^ "Grapefruit Benefits". 2022-11-17. Retrieved 2024-03-27.
  18. ^ Penniston KL, Nakada SY, Holmes RP, Assimos DG (2008). "Quantitative Assessment of Citric Acid in Lemon Juice, Lime Juice, and Commercially-Available Fruit Juice Products". Journal of Endourology. 22 (3): 567–570. doi:10.1089/end.2007.0304. PMC 2637791. PMID 18290732.
  19. ^ Ben Box, ed. (1993). "Costa Rica - The Meseta Central". 1994 Mexico & Central America Handbook. Sarah Cameron, Sebastian Ballard (4 ed.). Bath, England: Trade and Travel Publications Ltd. p. 682. ISBN 978-0900751462.
  20. ^ Monrose, Gregory Salomon (ed.). "Standardisation d'une formulation de confiture de chadèque et évaluation des paramètres physico-chimiques, microbiologiques et sensoriels" (in French). Université d'Etat d'Haiti (UEH / FAMV) - Ingenieur Agronome 2009. Archived from the original on 7 June 2017. Retrieved 5 June 2017 – via Memoire Online.
  21. ^ Bidault, Blandine; Gattegno, Isabelle, eds. (1984). Le point sur la transformation des fruits tropicaux (in French). Paris: Groupe de recherche et d'echanges technologiques (GRET). p. 46.
  22. ^ Zheng, Huiwen; Zhang, Qiuyun; Quan, Junping; Zheng, Qiao; Xi, Wanpeng (2016). "Determination of sugars, organic acids, aroma components, and carotenoids in grapefruit pulps". Food Chemistry. 205: 112–121. doi:10.1016/j.foodchem.2016.03.007. ISSN 0308-8146. PMID 27006221. S2CID 41172984.
  23. ^ A. Buettner; P. Schieberle (1999). "Characterization of the Most Odor-Active Volatiles in Fresh, Hand-Squeezed Juice of Grapefruit (Citrus paradisi Macfayden)". J. Agric. Food Chem. 47 (12): 5189–5193. doi:10.1021/jf990071l. PMID 10606593.
  24. ^ a b c d e Bailey, D. G.; Dresser, G.; Arnold, J. M. O. (2012). "Grapefruit-medication interactions: Forbidden fruit or avoidable consequences?". Canadian Medical Association Journal. 185 (4): 309–316. doi:10.1503/cmaj.120951. ISSN 0820-3946. PMC 3589309. PMID 23184849.
  25. ^ a b c d e f "Drug interactions with grapefruit juice". 18 May 2022. Retrieved 24 July 2023.
  26. ^ "How the "Don't take this medication with grapefruit juice" warning originated | Science-Based Medicine". 2022-09-29. Archived from the original on 2022-11-04. Retrieved 2022-11-04.
  27. ^ "Grapefruit production in 2022, Crops/Regions/World list/Production Quantity (pick lists)". UN Food and Agriculture Organization, Corporate Statistical Database (FAOSTAT). 2024. Retrieved 6 April 2024.
  28. ^ Xiaomeng Li; Rangjin Xie; Zhenhua Lu; Zhiqin Zhou. "Genetic origin of cultivated citrus determined: Researchers find evidence of origins of orange, lime, lemon, grapefruit, other citrus species". Science Daily. Archived from the original on 21 September 2017. Retrieved 21 September 2017.
  29. ^ a b Grapefruit: a fruit with a bit of a complex in Art Culinaire (Winter, 2007)
  30. ^ Kumamoto, J.; Scora, R. W.; Lawton, H. W.; Clerx, W. A. (1987-01-01). "Mystery of the forbidden fruit: Historical epilogue on the origin of the grapefruit, Citrus paradisi (Rutaceae)". Economic Botany. 41 (1): 97–107. doi:10.1007/BF02859356. ISSN 0013-0001. S2CID 42178548.
  31. ^ "World Wide Words: Grapefruit". World Wide Words. Archived from the original on 2021-03-09. Retrieved 2017-03-30.
  32. ^ Admin (2010). "Welchman Hall Gully, Barbados". Barbados National Trust. Archived from the original on 16 August 2010. Retrieved 11 July 2010. The Development of the Gully - The Gully was once part of a plantation owned by a Welshman called General William Asygell Williams over 200 years ago. Hence the name "Welchman Hall" gully. It was this man who first developed the gully with exotic trees and an orchard. Interestingly, the grapefruit is originally from Barbados and is rumoured to have started in Welchman Hall Gully.
  33. ^ Bowman, Kim D.; Gmitter, Frederick Jr. (April 1990). "Forbidden Fruit (Citrus sp., Rutaceae) Rediscovered in Saint Lucia". Economic Botany. 44 (2): 165–173. doi:10.1007/BF02860484. JSTOR 4255226. S2CID 33098910. Archived from the original on 2022-04-11. Retrieved 2022-04-11.
  34. ^ Lunan, John (1814). Hortus Jamaicensis. Jamaica: St. Iago de la Vega Gazette. pp. 171–173. Archived from the original on 27 July 2020. Retrieved 24 December 2020.
  35. ^ "How did the grapefruit get its name?". Library of Congress. Everyday Mysteries. Archived from the original on November 27, 2020. Retrieved January 26, 2021.
  36. ^ Macfadyen, J 1830. Some remarks on the species of genus Citrus which are cultivated in Jamaica. Bot. Misc. 1:295–304.
  37. ^ California (1895). "Report of the Secretary–the pomelo". Appendix to the Journals of the Senate and Assembly of the twenty-first Session of the Legislature of the State of California. Vol. V. Sacramento, California: Legislature of the State of California. p. 65. Archived from the original on 2023-07-13. Retrieved 2020-10-07. The pomelo is now marketed under the name "grape-fruit," which is a misnomer. This is confusing and misleading. The name "grape-fruit" was given to this fruit in Florida, as it hangs on trees in clusters resembling the grape, but has no relation to it whatever. Growers and shippers should drop the name "grape-fruit" and apply to it the name pomelo, which is popular, and botanically correct.
  38. ^ "Texas Citrus: Puzzling Beginnings". Archived from the original on 2007-01-25. Retrieved 2007-03-02.
  39. ^ University of Florida: IFAS Extension; The Grapefruit. "Fact Sheet" (PDF). Archived from the original (PDF) on 2007-06-28.
  40. ^ "Manatee County a big part of citrus history". 2004-08-16. Archived from the original on 2012-10-12. Retrieved 2011-12-17.
  41. ^ a b c d e f Morton, Julia F. (1987). "Tangelo; In: Fruits of Warm Climates". Miami, Florida. pp. 158–160. ISBN 0-9610184-1-0. Archived from the original on 2019-10-09. Retrieved 2019-09-30.