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). One story of the fruit's origins is that a certain "Captain Shaddock" brought pomelo seeds to Jamaica and bred the first fruit. However, it probably originated as a naturally-occurring hybrid.
The hybrid fruit was documented in 1750 by a Welshman, Rev. Griffith Hughes, who described specimens from Barbados. Currently, the grapefruit is said to be one of the "Seven Wonders of Barbados." It was brought to Florida by Count Odette Philippe in 1823 in what is now known as Safety Harbor. Further crosses have produced the tangelo (1905), the Minneola tangelo (1931), and the oroblanco (1984).
The grapefruit was known as the shaddock or shattuck until the 19th century. Its current name alludes to clusters of the fruit on the tree, which often appear similar to grapes. Botanically, it was not distinguished from the pomelo until the 1830s, when it was given the name Citrus paradisi. 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.
An early pioneer in the American citrus industry was Kimball Chase Atwood, a wealthy entrepreneur who founded the Atwood Grapefruit Co. in the late 19th century. The Atwood Grove became the largest grapefruit grove in the world, with an annual production of 80,000 boxes of fruit. It was there that pink grapefruit was first discovered in 1906.
The 1929 Ruby Red patent was associated with real commercial success, which came after the discovery of a red grapefruit growing on a pink variety. Only with the introduction of the Ruby Red did the grapefruit transform into a real agricultural success. The Red grapefruit, starting with the Ruby Red, has even become a symbolic fruit of Texas, where white "inferior" grapefruit were eliminated and only red grapefruit were grown for decades. Using radiation to trigger mutations, new varieties were developed to retain the red tones which typically faded to pink, the Rio Red variety is the current (2007) Texas grapefruit with registered trademarks Rio Star and Ruby-Sweet, also sometimes promoted as "Reddest" and "Texas Choice".
The Florida Department of Citrus states "the primary varieties of Florida grapefruit are Ruby Red, Pink, Thompson, Marsh and Duncan. The fresh grapefruit season typically runs from October through June. - Wikipedia, History Of Grapefruit.
Influenza: Grapefruit is a valuable remedy for influenza as it helps to minimize acidity from the system. The bitter properties arising from an essence called 'maringin' in grapefruit tones up the system and the digestive swathe.
Malaria: The juice or the fruit itself consists of valuable and natural 'quinine' which are advantageous for the treatment of malaria. The quinine can be easily extracted from the fruits by boiling a quarter of grapefruit and spraining the pulp.
Acidity: The fresh grapefruit juice has alkaline reaction after digestion. The citric acid of the fruit is tarnished in the human body and thus, increases the effect of the alkalinity reaction after digestion. The juice extracted from the grapefruit is beneficial in preventing the acid formation and many other diseases that arise due to the presence of acidity in the body. - Organic Facts
Grapefruits contains high amounts of a flavanoid called naringenin. - Nutrition & You
Naringenin suppress colon carcinogenesis (colon cancer) through the aberrant crypt stage in azoxymethane-treated rats. - Leonardi T, Vanamala J, Taddeo SS, Davidson LA, Murphy ME, Patil BS, Wang N, Carroll RJ, Chapkin RS,Lupton JR, Turner ND
Naringenin reduces lung metastasis in a breast cancer resection model .- Qin L, Jin L, Lu L, Lu X, Zhang C, Zhang F, Liang W
The rich pink and red colors of grapefruit are due to lycopene, a carotenoid phytonutrient. Lycopene appears to have anti-tumor activity. Among the common dietary carotenoids, lycopene has the highest capacity to help fight oxygen free radicals, which are compounds that can damage cells and cause cancer.
Choosing to regularly eat lycopene-rich foods, such as pink grapefruit, and drink green tea may greatly reduce a man's risk of developing prostate cancer - Asia Pacific Journal of Clinical Nutrition
Phytonutrients in grapefruit called limonoids inhibit tumor formation by promoting the formation of glutathione-S-transferase, a detoxifying enzyme. This enzyme sparks a reaction in the liver that helps to make toxic compounds more water soluble for excretion from the body. Pulp of citrus fruits like grapefruit contain glucarates, compounds that may help prevent breast cancer.
In animal studies and laboratory tests with human cells, limonoids have been shown to help fight cancers of the mouth, skin, lung, breast, stomach and colon. - Worlds Healthiest Foods