Flavorful and nutritious – it's easy to understand why grapefruits are no
longer just a breakfast option. Half a grapefruit provides more than 45
percent of the adult Recommended Daily Allowance (RDA) of vitamin C; it also
has 175 mg of potassium and 1 mg of iron. The pink and red varieties are
high in beta carotene, which the body then converts to vitamin A.
A cup of
unsweetened grapefruit juice has 95 mg of vitamin C, more than 100 percent
of the RDA, and most of the other nutrients found in the fresh fruit. In the
past, many people shunned the unsweetened grapefruit juice because of its
tartness, but a naturally sweet juice can be made by using the red or pink
Over the years a number of fad diets have promoted the
grapefruit as possessing a unique ability to burn away fat. there is no
truth to these claims; no food can do this. People following grapefruit
diets lose weight because they eat little else – a practice that can lead to
nutritional deficiencies. Even so, grapefruits are a good food to include in
a sensible weight-loss diet; a serving contains less than 100 calories, and
its high-fiber content satisfies hunger.
Grapefruits are especially high
in pectin, a soluble fiber that helps lower blood cholesterol. In addition,
recent studies indicate that grapefruits contain other substances that
prevent disease. Pink and red grapefruits, for example, are high in lycopene,
an antioxidant that appears to lower the risk of prostate cancer.
Researchers have not yet identified lycopene's mechanism of action, but a
6-year Harvard study involving 48,000 doctors and other health professionals
has linked 10 servings of lycopene-rich foods a week with a 50 percent
reduction in prostate cancer.
Other protective plant chemicals found in
grapefruits include phenolic acid, which inhibits the formation of
cancer-causing nitrosamines; limonoids, terpenes, and monoterpenes, which
induce the production of enzymes that help prevent cancer; and bioflavonoids,
which inhibit the action of hormones that promote tumor growth. Some people
with rheumatoid arthritis, lupus, and other inflammatory disorders find that
eating grapefruit daily seems to alleviate their symptoms. this may occur
because plant chemicals block the prostaglandins that cause inflammation.
Those people who are allergic to other citrus fruits are likely to react to
grapefruits, too. The sensitivity may be to the fruit itself or to an oil in