See ACICLOVIR.
Nutritional Profile Energy value (calories per serving): Low Protein: High Fat: Low Saturated fat: Low Cholesterol: None Carbohydrates: Moderate Fiber: Very high Sodium: Low Major vitamin contribution: Vitamin A, folate, vitamin C Major mineral contribution: Calcium
About the Nutrients in This Food Broccoli is very high-fiber food, an excellent source of vitamin A, the B vitamin folate, and vitamin C. It also has some vitamin E and vitamin K, the blood-clotting vitamin manufactured primarily by bacteria living in our intestinal tract. One cooked, fresh broccoli spear has five grams of dietary fiber, 2,500 IU vitamin A (108 percent of the R DA for a woman, 85 percent of the R DA for a man), 90 mcg folate (23 percent of the R DA), and 130 mg vitamin C (178 percent of the R DA for a woman, 149 percent of the R DA for a man).
The Most Nutritious Way to Serve This Food Raw. Studies at the USDA Agricultural Research Center in Beltsville, Maryland, show that raw broccoli has up to 40 percent more vitamin C than broccoli that has been cooked or frozen.
Diets That May Restrict or Exclude This Food Antiflatulence diet Low-fiber diet
Buying This Food Look for: Broccoli with tightly closed buds. The stalk, leaves, and florets should be fresh, firm, and brightly colored. Broccoli is usually green; some varieties are tinged with purple. Avoid: Broccoli with woody stalk or florets that are open or turning yellow. When the green chlorophyll pigments fade enough to let the yellow carotenoids underneath show through, the buds are about to bloom and the broccoli is past its prime.
Storing This Food Pack broccoli in a plastic bag and store it in the refrigerator or in the vegetable crisper to protect its vitamin C. At 32°F, fresh broccoli can hold onto its vitamin C for as long as two weeks. Keep broccoli out of the light; like heat, light destroys vitamin C.
Preparing This Food First, rinse the broccoli under cool running water to wash off any dirt and debris clinging to the florets. Then put the broccoli, florets down, into a pan of salt water (1 tsp. salt to 1 qt. water) and soak for 15 to 30 minutes to drive out insects hiding in the florets. Then cut off the leaves and trim away woody section of stalks. For fast cooking, divide the broccoli up into small florets and cut the stalk into thin slices.
What Happens When You Cook This Food The broccoli stem contains a lot of cellulose and will stay firm for a long time even through the most vigorous cooking, but the cell walls of the florets are not so strongly fortified and will soften, eventually turning to mush if you cook the broccoli long enough. Like other cruciferous vegetables, broccoli contains mustard oils (isothiocyanates), natural chemicals that break down into a variety of smelly sulfur compounds (including hydrogen sulfide and ammonia) when the broccoli is heated. The reaction is more intense in aluminum pots. The longer you cook broccoli, the more smelly compounds there will be, although broccoli will never be as odorous as cabbage or cauliflower. Keeping a lid on the pot will stop the smelly molecules from floating off into the air but will also accelerate the chemical reaction that turns green broccoli olive-drab. Chlorophyll, the pigment that makes green vegetables green, is sensitive to acids. When you heat broccoli, the chlorophyll in its florets and stalk reacts chemically with acids in the broccoli or in the cooking water to form pheophytin, which is brown. The pheophytin turns cooked broccoli olive-drab or (since broccoli contains some yellow carotenes) bronze. To keep broccoli green, you must reduce the interaction between the chlorophyll and the acids. One way to do this is to cook the broccoli in a large quantity of water, so the acids will be diluted, but this increases the loss of vitamin C.* Another alternative is to leave the lid off the pot so that the hydrogen atoms can float off into the air, but this allows the smelly sulfur compounds to escape, too. The best way is probably to steam the broccoli quickly with very little water, so it holds onto its vitamin C and cooks before there is time for reac- tion between chlorophyll and hydrogen atoms to occur.
How Other Kinds of Processing Affect This Food Freezing. Frozen broccoli usually contains less vitamin C than fresh broccoli. The vitamin is lost when the broccoli is blanched to inactivate catalase and peroxidase, enzymes that would otherwise continue to ripen the broccoli in the freezer. On the other hand, according to researchers at Cornell University, blanching broccoli in a microwave oven—two cups of broccoli in three tablespoons of water for three minutes at 600 –700 watts—nearly doubles the amount of vitamin C retained. In experiments at Cornell, frozen broccoli blanched in a microwave kept 90 percent of its vitamin C, compared to 56 percent for broccoli blanched in a pot of boiling water on top of a stove.
Medical Uses and/or Benefits Protection against some cancers. Naturally occurring chemicals (indoles, isothiocyanates, glucosinolates, dithiolethiones, and phenols) in Brussels sprouts, broccoli, cabbage, cauli- flower, and other cruciferous vegetables appear to reduce the risk of some forms of cancer, perhaps by preventing the formation of carcinogens in your body or by blocking cancer- causing substances from reaching or reacting with sensitive body tissues or by inhibiting the transformation of healthy cells to malignant ones. All cruciferous vegetables contain sulforaphane, a member of a family of chemicals known as isothiocyanates. In experiments with laboratory rats, sulforaphane appears to increase the body’s production of phase-2 enzymes, naturally occurring substances that inacti- vate and help eliminate carcinogens. At the Johns Hopkins University in Baltimore, Maryland, 69 percent of the rats injected with a chemical known to cause mammary cancer developed tumors vs. only 26 percent of the rats given the carcinogenic chemical plus sulforaphane. To get a protective amount of sulforaphane from broccoli you would have to eat about two pounds a week. But in 1997, Johns Hopkins researchers discovered that broccoli seeds and three-day-old broccoli sprouts contain a compound converted to sulforaphane when the seed and sprout cells are crushed. Five grams of three-day-old sprouts contain as much sulphoraphane as 150 grams of mature broccoli. * Broccoli will lose large amounts of vitamin C if you cook it in water t hat is cold when you start. As it boils, water releases ox ygen t hat would ot her wise dest roy vitamin C, so you can cut t he vitamin loss dramat ically simply by lett ing t he water boil for 60 seconds before adding t he broccoli. Vision protection. In 2004, the Johns Hopkins researchers updated their findings on sulfora- phane to suggest that it may also protect cells in the eyes from damage due to ultraviolet light, thus reducing the risk of macular degeneration, the most common cause of age-related vision loss. Lower risk of some birth defects. Up to two or every 1,000 babies born in the United States each year may have cleft palate or a neural tube (spinal cord) defect due to their mothers’ not having gotten adequate amounts of folate during pregnancy. The current R DA for folate is 180 mcg for a woman, 200 mcg for a man, but the FDA now recommends 400 mcg for a woman who is or may become pregnant. Taking a folate supplement before becoming pregnant and continuing through the first two months of pregnancy reduces the risk of cleft palate; taking folate through the entire pregnancy reduces the risk of neural tube defects. Broccoli is a good source of folate. One raw broccoli spear has 107 mcg folate, more than 50 percent of the R DA for an adult. Possible lower risk of heart attack. In the spring of 1998, an analysis of data from the records for more than 80,000 women enrolled in the long-running Nurses’ Health Study at Harvard School of Public Health/Brigham and Women’s Hospital, in Boston, demonstrated that a diet providing more than 400 mcg folate and 3 mg vitamin B6 daily, either from food or supple- ments, might reduce a woman’s risk of heart attack by almost 50 percent. Although men were not included in the study, the results were assumed to apply to them as well. However, data from a meta-analysis published in the Journal of the American Medical Association in December 2006 called this theory into question. Researchers at Tulane Univer- sity examined the results of 12 controlled studies in which 16,958 patients with preexisting cardiovascular disease were given either folic acid supplements or placebos (“look-alike” pills with no folic acid) for at least six months. The scientists, who found no reduction in the risk of further heart disease or overall death rates among those taking folic acid, concluded that further studies will be required to ascertain whether taking folic acid supplements reduces the risk of cardiovascular disease. Possible inhibition of the herpes virus. Indoles, another group of chemicals in broccoli, may inhibit the growth of some herpes viruses. In 2003, at the 43rd annual Interscience Confer- ence on Antimicrobial Agents and Chemotherapy, in Chicago, researchers from Stockholm’s Huddinge University Hospital, the University of Virginia, and Northeastern Ohio University reported that indole-3-carbinol (I3C) in broccoli stops cells, including those of the herpes sim- plex virus, from reproducing. In tests on monkey and human cells, I3C was nearly 100 percent effective in blocking reproduction of the HSV-1 (oral and genital herpes) and HSV-2 (genital herpes), including one strain known to be resistant to the antiviral drug acyclovir (Zovirax).
Adverse Effects Associated with This Food Enlarged thyroid gland. Cruciferous vegetables, including broccoli, contain goitrin, thio- cyanate, and isothiocyanate, chemical compounds that inhibit the formation of thyroid hormones and cause the thyroid to enlarge in an attempt to produce more. These chemicals, known collectively as goitrogens, are not hazardous for healthy people who eat moderate amounts of cruciferous vegetables, but they may pose problems for people who have thyroid problems or are taking thyroid medication. False-positive test for occult blood in the stool. The guaiac slide test for hidden blood in feces relies on alphaguaiaconic acid, a chemical that turns blue in the presence of blood. Broccoli contains peroxidase, a natural chemical that also turns alphaguaiaconic acid blue and may produce a positive test in people who do not actually have blood in the stool.
Food/Drug Interactions Anticoagulants Broccoli is rich in vitamin K, the blood-clotting vitamin produced natu- rally by bacteria in the intestines. Consuming large quantities of this food may reduce the effectiveness of anticoagulants (blood thinners) such as warfarin (Coumadin). One cup of drained, boiled broccoli contains 220 mcg vitamin K, nearly four times the R DA for a healthy adult.... broccoli
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