Short answers, pulled from the story.
Griffith Hughes documented the grapefruit in 1750 while describing a strange citrus plant in Barbados that he called the forbidden fruit. This early account described a fruit that was neither fully sweet nor entirely sour and existed in a liminal space between the pomelo and the sweet orange. The plant grew in clusters that resembled bunches of grapes, leading to its eventual name.
The grapefruit is a genetic accident born from the collision of the Indonesian pomelo and the Jamaican sweet orange in the West Indies. The female parent was the Indonesian pomelo introduced to the Caribbean from Asia in the 17th century, and the male parent was the Jamaican sweet orange that arrived by 1692. The Scottish physician and botanist James Macfadyen gave the resulting offspring the scientific name Citrus paradisi in 1830.
The British naturalist John Lunan published the term grapefruit in 1814 to describe a similar Jamaican citrus plant. The name derived from the fruit's similarity in taste to the grape or alludes to the clusters of fruit on the tree which often appear similar to bunches of grapes. The name grape-fruit was used during the 19th century to refer to pomelos before the true origins were determined in the 1940s.
A pink grapefruit was discovered in the Atwood Grove in 1906 by Kimball Chase Atwood who founded the Atwood Grapefruit Company. The discovery marked a turning point as the red and pink varieties were generally sweeter than the white varieties and led to the 1929 Ruby Red patent. The Texas Legislature designated this variety the official State Fruit of Texas in 1993.
Grapefruit juice contains furanocoumarins specifically bergamottin and 6',7'-dihydroxybergamottin which inhibit the CYP3A4 enzyme responsible for metabolizing 90% of drugs. This inhibition can lead to adverse effects such as abnormal heart rhythms, bleeding inside the stomach, low blood pressure, difficulty breathing, and dizziness. One whole grapefruit or a glass of grapefruit juice is enough to cause drug overdose toxicity.
World production of grapefruits combined with pomelos reached 9.93 million tonnes in 2023 with China leading the market at 52% of the total. Vietnam serves as a secondary producer while the evergreen grapefruit trees usually grow to around 15 to 20 feet tall. The fruit is yellow-orange skinned and generally an oblate spheroid in shape ranging in diameter from 4 to 6 inches.