Onions, sweet, raw
106 calories in a whole onion. Considered a zero calorie food, which means you can eat as much of them as you possibly can and still lose weight. They are excellent chopped up in Salad Nicoise.
Onions are a very good source of vitamin C, chromium and dietary fiber.They are also a good source of manganese, molybdenum, vitamin B6,folate, potassium, phosphorous and copper.
Health Benefits Of Onions:
Onions, like garlic, are members of the Allium family, and both arerich in powerful sulfur-containing compounds that are responsible fortheir pungent odors and for many of their health-promoting effects.Onions contain allyl propyl disulphide, while garlic is rich in allicin, diallyl disulphide, diallyl trisulfideand others. In addition, onions are very rich in chromium, a tracemineral that helps cells respond to insulin, plus vitamin C, andnumerous flavonoids, most notably, quercitin.
Blood Sugar-Lowering Effects
The higher the intake of onion, the lower the level of glucose foundduring oral or intravenous glucose tolerance tests. Experimental andclinical evidence suggests that allyl propyl disulfide is responsiblefor this effect and lowers blood sugar levels by increasing the amountof free insulin available. Allyl propyl disulfide does this bycompeting with insulin, which is also a disulphide, to occupy the sitesin the liver where insulin is inactivated. This results is an increasein the amount of insulin available to usher glucose into cells causinga lowering of blood sugar.
In addition, onions are a very good source of chromium, themineral component in glucose tolerance factor, a molecule that helpscells respond appropriately to insulin. Clinical studies of diabeticshave shown that chromium can decrease fasting blood glucose levels,improve glucose tolerance, lower insulin levels, and decrease totalcholesterol and triglyceride levels, while increasing goodHDL-cholesterol levels. Marginal chromium deficiency is common in theUnited States, not surprising since chromium levels are depleted by theconsumption refined sugars and white flour products as well as the lackof exercise. One cup of raw onion contains over 20% of the Daily Valuefor this important trace mineral.
Cardiovascular Benefits
The regular consumption of onions has, like garlic, been shown tolower high cholesterol levels and high blood pressure, both of whichhelp prevent atherosclerosis and diabetic heart disease, and reduce therisk of heart attack or stroke. These beneficial effects are likely dueto onions' sulfur compounds, its chromium and its vitamin B6, whichhelps prevent heart disease by lowering high homocysteine levels,another significant risk factor for heart attack and stroke.Onions have been singled out as one of the small numberof vegetables and fruits that contributed to the significant reductionin heart disease risk seen in a meta-analysis of seven prospectivestudies. Of the more than 100,000 individuals who participated in thesestudies, those who diets most frequently included onions, tea, applesand broccoli-the richest sources of flavonoids-gained a 20% reductionin their risk of heart disease.
Support Gastrointestinal Health
The regular consumption of onions, as little as two or more timesper week, is associated with a significantly reduced risk of developingcolon cancer. Onions contain a number of flavonoids, the most studiedof which, quercitin, has been shown to halt the growth of tumors inanimals and to protect colon cells from the damaging effects of certaincancer-causing substances. Cooking meats with onions may help reducethe amount of carcinogens produced when meat is cooked using high heatmethods.Quercitin, an antioxidant in onions, and curcumin, a phytonutrientfound in the curry spice turmeric, reduce both the size and number ofprecancerous lesions in the human intestinal tract, suggests researchpublished in Clinical Gasteroenterology and Hepatology.
Five patients with an inherited form of precancerous polyps inthe lower bowel known as familial adenomatous polyposis (FAP) weretreated with regular doses of curcumin and quercetin over an average ofsix months. The average number of polyps dropped 60.4%, and the averagesize of the polyps that did develop dropped by 50.9%.
FAP runs in families and is characterized by the development ofhundreds of polyps (colorectal adenomas) and, eventually, colon cancer.Recently, nonsteroidal anti-inflammatory drugs (NSAIDs such as aspirin,ibuprofen) have been used to treat some patients with this condition,but these drugs often produce significant side effects, includinggastrointestinal ulcerations and bleeding, according to lead researcherFrancis M. Giardiello, M.D., at the Division of Gastroenterology, JohnsHopkins University.
Previous observational studies in populations that consumelarge amounts of curry, as well as animal research, have stronglysuggested that curcumin, one of the main ingredients in Asian curries,might be effective in preventing and/or treating cancer in the lowerintestine. Similarly, quercetin, an anti-oxidant flavonoid found in avariety of foods including onions, green tea and red wine, has beenshown to inhibit growth of colon cancer cell lines in humans andabnormal colorectal cells in animals.
In this study, a decrease in polyp number was observed in fourof five patients at three months and four of four patients at sixmonths.
Each patient received curcumin (480 mg) and quercetin (20 mg)orally 3 times a day for 6 months. Although the amount of quercetin wassimilar to what many people consume daily, the curcumin consumed wasmore than would be provided in a typical diet because turmeric onlycontains on average 3-5 % curcumin by weight.While simply consuming curry and onions may not have as dramatic aneffect as was produced in this study, this research clearlydemonstrates that liberal use of onions and turmeric and onions canplay a protective role against the development of colorectal cancer.
Onion and Garlic Protective against Many Cancers
Making onion and garlic a staple in your healthy way of eating maygreatly lower your risk of several common cancers, suggests a largedata set of case-control studies from Southern European populations(Galeone C, Pelucchi C et al, American Journal of Clinical Nutrition).
Study participants consuming the most onions showed an 84% reduced riskfor cancer of the oral cavity and pharynx, 88% reduced risk foresophageal cancer, 56% reduced risk for colorectal cancer, 83% reducedrisk for laryngeal cancer, 25% reduced risk for breast cancer, 73%reduced risk for ovarian cancer, 71% reduced risk for prostate cancer,and 38% reduced risk for renal cell cancer, compared to those eatingthe least onions.
Similarly, those eating the most garlic had a 39% reduced risk forcancer of the oral cavity and pharynx, 57% reduced risk for esophagealcancer, 26% reduced risk for colorectal cancer, 44% reduced risk forlaryngeal cancer, 10% reduced risk for breast cancer, 22% reduced riskfor ovarian cancer, 19% reduced risk for prostate cancer, and 31%reduced risk for renal cell cancer, compared to those eating the leastgarlic.
Boost Bone Health
Milk isn't the only food that boosts bone health. Onions also help maintain healthy bones, suggests a study published in the Journal of Agricultural and Food Chemistry.A compound newly identified in onions with the long complex name of gamma-L-glutamyl-trans-S-1-propenyl-L-cysteinesulfoxide, GPCS, for short, inhibits the activity of osteoclasts (thecells that break down bone). The more GPCS given in this animal study,the more the bone resorptive (breakdown) action of osteoclasts wasinhibited.
Onions may be especially beneficial for women, who are atincreased risk for osteoporosis as they go through menopause.Fosamax (Alendronate), the drug typically prescribed to preventexcessive bone loss, works in a similar manner, by destroyingosteoclasts, so they do not break down bone. Potential negative sideeffects of Fosamax include irritation of the upper gastrointestinalmucosa, acid regurgitation, esophageal ulcers and erosions. Potentialnegative side effects of eating onions: onion breath.
Anti-Inflammatory and Anti-Bacterial Activity
Several anti-inflammatory agents in onions render them helpful inreducing the severity of symptoms associated with inflammatoryconditions such as the pain and swelling of osteo- and rheumatoidarthritis, the allergic inflammatory response of asthma, and therespiratory congestion associated with the common cold. Both onions andgarlic contain compounds that inhibit lipoxygenase and cyclooxygenase(the enzymes that generate inflammatory prostaglandins andthromboxanes), thus markedly reducing inflammation. Onions'anti-inflammatory effects are due not only to their vitamin C andquercitin, but to other active components called isothiocyanates.These compounds work synergistically to spell relief from inflammation.In addition, quercitin and other flavonoids found in onions work withvitamin C to help kill harmful bacteria, making onions an especiallygood addition to soups and stews during cold and flu season.
Description
Onions may bring a tear to your eye, and a pungency to your breath,but they will most certainly bring delight to your tastebuds. Theonion, known scientifically as Allium cepa, is, on the surface,a humble brown, white or red, paper-thin skinned bulb; yet, despite itsplain looks, has an intense flavor and is a beloved part of the cuisineof almost every region of the world. The word onion comes from theLatin word unio for "single," or "one," because the onion plantproduces a single bulb, unlike its cousin, the garlic, that producesmany small bulbs. The name also describes the onion bulb when cut downthe middle; it is a union (also from unio) of many separate, concentrically arranged layers.
Onions range in size, color and taste depending upon theirvariety. There are generally two types of large, globe-shaped onions,classified as spring/summer or storage onions. The former classincludes those that are grown in warm weather climates and havecharacteristic mild or sweet tastes. Included in this group are theMaui Sweet Onion (in season April through June), Vidalia (in season Maythrough June) and Walla Walla (in season July and August). Storageonions are grown in colder weather climates and, after harvesting, aredried out for a period of several months, attaining dry, crisp skins.They generally have a more pungent flavor and are usually named bytheir color: white, yellow or red. Spanish onions fall into thisclassification. In addition to these large onions, there are alsosmaller varieties such as the green onion, or scallion, and the pearlonion.
