Grapefruit: Nutrition Facts
Grapefruit is a popular citrus fruit that is a terrific source of vitamins, fiber and other nutrients. Grapefruit is also known for its antioxidants and immunities- boosting capabilities as well as its digestive and cholesterol lowering benefits.
Grapefruit gets its name from the way it grows (on tree branches in grape like clusters), according to the Library of Congress.
Grapefruit is an accidental hybrid between the orange and the pomelo, but no one is sure when it was first grown. It was first documented in 1750 by a Welshman in Barbados who described it as a “forbidden fruit,” according to the Purdue University horticulture department. Until the 19th century, it was also called the shaddock, named after a sea captain who is said to have brought the seeds of a pomelo to Jamaica. It has also been called paradise fruit. It was given the scientific name, Citrus paradisi, but in the 1940s when research confirmed that it was hybrid, the name was changed to Citrus x paradisi — the x indicates that it is a hybrid.
According to the George Mateljan Foundation’s World’s Healthiest Foods website, half a medium-size grapefruit provides 59 percent of your daily vitamin C needs.
“Vitamin C is plays a role in immunity and helps neutralize free radicals in our body,” said Rumsey. According to the Linus Pauling Institute at Oregon State University, vitamin C stimulates the production of white blood cells and may protect the integrity of immune cells. Vitamin C helps also protect leukocytes, which produces antiviral substances.
An article in the Journal of Agricultural and Food Chemistry evaluated the phenolic compounds in 13 fruit juices. Grapefruit juice is ranked amongst the best juices. Phenolic compounds act as antioxidants, which are molecules that safely interact with free radicals to stop the condition of oxidative stress, according to an article in Pharmacognosy Review. Free radicals cause cell damage and disruption that can contribute to diseases. Vitamin C is also a potent antioxidant.
The fiber and water in grapefruit can aid digestion and help relieve or prevent constipation.
“Grapefruit is naturally high in fiber, which contributes to feelings of satiation which can prevent overeating,” said Rumsey. “Fiber also helps stabilize blood sugar levels, preventing spikes that contribute to hunger.”
A study published in the Journal of Medicinal Food looked at 91 obese patients who took either grapefruit capsules, grapefruit juice, half of a fresh grapefruit or placebo capsules. All grapefruit-taking patients lost more weight than the placebo group, with those eating fresh grapefruit losing the most and those drinking grapefruit juice losing nearly as much. The grapefruit groups also saw improved insulin resistance and metabolic syndrome.
“Grapefruit contains pectin, a fiber that is can reduce LDL cholesterol levels and decrease triglycerides,” said Rumsey. A study published in the Journal of Agricultural and Food Chemistry looked at 57 hyperlipidemic patients after coronary bypass surgery and found that supplementing their diets with either white or red grapefruit every day for 30 days lowered LDL cholesterol levels. Eating red grapefruit lowered LDL cholesterol levels more, and also lowered triglycerides.