kdelca7470
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Subject: Vitamin C
What Is It?
In the eighteenth century, seasoned sailors found that by sucking on lemons they could avoid scurvy, a debilitating disease that often developed during long voyages when fresh fruits and vegetables were scarce. When the lemon's key nutrient was formally identified in 1928, it was named ascorbic acid for its anti-scurvy, or antiscorbutic, action. Today ascorbic acid is widely known as vitamin C.
Health Benefits
The health benefits of vitamin C are abundant and varied, but it's probably best known as a cell protector, immunity booster, and powerful antioxidant. The body's ligaments, tendons, and collagen (a protein found in connective tissues) rely on the presence of vitamin C to stay strong and healthy. Like all antioxidants, vitamin C counters the effects of cell-damaging molecules called free radicals. As an added benefit, it even helps the body recycle other antioxidants. For certain conditions, vitamin C is best taken with other antioxidants, such as vitamin E, flavonoids, and carotendoids.
Specifically, vitamin C may help to:
Lessen the severity and duration of colds and flu. Taking vitamin C at the first sign of a cold or the flu may keep the illness from fully developing, and you'll probably recover faster. In a 1995 review of studies investigating the effect of vitamin C on colds, researchers concluded that doses of 1,000 to 6,000 mg a day at the onset of symptoms reduced a cold's duration by 21%, and shortened its duration by one day on average. Taking vitamin C doesn't prevent colds, however.
Speed wound healing and minimize the effects of bruising. Vitamin C helps the body to repair and maintain itself by reinforcing cell walls and helping to strengthen tiny blood vessels called capillaries. It further accelerates healing by inhibiting inflammation.
Keep gums strong and healthy. When taken daily, vitamin C protects gum tissue against cell damage and speeds healing in this delicate area. It's often taken with flavonoids for this purpose. Brushing the gums with vitamin C powder can also minimize inflammation and bleeding.
Increase resistance to heart disease (and angina) by improving cholesterol levels. Several studies have linked the presence of low levels of vitamin C to a greater risk of angina and heart attacks in people with existing heart disease. Research also indicates that, when taken with vitamin E, vitamin C helps protect LDL ("bad") cholesterol from oxidation, thus preventing plaque buildup in coronary arteries. Vitamin C may also boost blood levels of HDL ("good") cholesterol; studies are ongoing to provide definitive evidence of this action.
Prevent certain cancers. As a powerful antioxidant, vitamin C may help to fight cancer by protecting healthy cells from free-radical damage and inhibiting the proliferation of cancerous cells. Specifically, recent studies have shown that the vitamin may help stave off cancers of the stomach and esophagus by blocking the conversion of nitrates and nitrites into cancer-causing compounds. Debate over the value of vitamin C for cancer treatment and prevention is fierce, however, with some studies finding no benefit—or even drawbacks—from vitamin C supplementation, while others report prolonged survival in cancer patients, especially when it's taken along with vitamin E.
Protect against cataracts. Vitamin C may keep the lens of the eye from being damaged by cigarette smoke and ultraviolet (UV) light, both types of exposure linked to cataract formation. One study showed that women who took vitamin C supplements for 10 years or more had a 77% lower risk of "lens opacities," the beginning stage of cataracts, than women who didn't use supplements.
Relieve allergies, eczema, sinusitis, and asthma. Vitamin C is a natural antihistamine capable of blocking the effect of inflammatory substances some people produce in response to allergens such as pollen and pet dander. Allergies are often an underlying cause of sinusitis and may also trigger the intensely itchy rashes associated with eczema. Vitamin C is frequently recommended with other antioxidants such as flavonoids for sinusitis. Numerous studies have shown that vitamin C helps prevent or improve asthmatic symptoms as well; asthma sufferers are often deficient in this and other vitamins. Vitamin C has also been shown to help exercise-induced asthma attacks, in some cases thwarting an attack if taken in an adequate dose right before a workout. Adults with exercise-induced asthma may want to experiment with doses from 500 mg to 5000 mg.
Prevent migraines. Taken along with pantothenic acid, vitamin C boosts the production of hormones that help the body deal with the adverse effects of stress-induced migraines.
Improve memory. As an antioxidant, vitamin C plays a key role in maintaining healthy nerve cells, and is often taken in combination with vitamin E, mixed carotenoids, ginkgo biloba, and coenzyme Q10 to help prevent memory loss.
Fight chronic fatigue syndrome. Vitamin C taken with mixed carotenoids helps strengthen a weakened immune system, believed by many to be a factor in this disabling disorder.
Control gallstone formation. Sometimes gallstones develop when bile contains high concentrations of cholesterol. Vitamin C may help to lower the risk of this occurring by reducing bile cholesterol levels.
Combat the effects of aging and extend life. Used in combination with other antioxidants, such as vitamin E and flavonoids, vitamin C may combat the deteriorative effects of aging (such as wrinkles) caused by free-radical damage. It may also help you live longer. In one study, men who took more than 300 mg of vitamin C a day (from food and supplements) lived longer than men who consumed less than 50 mg a day.
Forms
tablet
powder
liquid
capsule
Recommended Intake
The RDA for vitamin C for nonsmoking men and women is 60 mg a day (for smokers it's 100 mg). Recently experts have strongly suggested increasing the RDA to between 100 and 200 mg a day for all adults, and many recommend getting much more of this vitamin to maximize its health benefits.
If You Get Too Little
The chances of getting scurvy today are all but nonexistent, because just 10 mg of vitamin C a day prevents this disease. Less than 50 mg a day, however, can result in an increased risk of heart attack, cataracts, and a reduced life span.
If You Get Too Much
Because vitamin C is water-soluble—what the body cannot use, it eliminates in the urine and feces in about 12 hours—it's hard to get too much. But while many people are able to tolerate high doses of vitamin C (as much as 6,000 mg a day) with no ill effects, others may suffer from mouth ulcers, diarrhea, gas, and bloating at doses above 2,000 mg; these problems subside when the dose is reduced.
General Dosage Information
Special tip: Consider taking vitamin C as part of an antioxidant formula. It works best in concert with other antioxidants, especially vitamin E and flavonoids. The flavonoids, sometimes labeled as bioflavonoids, also enhance the effectiveness of vitamin C.
For general health: Make sure you get 500 mg a day through foods and supplements.
For the treatment of various diseases: Depending on the ailment, 1,000 to 6,000 mg may be appropriate.
Be sure to check out our Dosage Recommendations Chart for Vitamin C, which lists therapeutic dosages for specific ailments at a glance.
Guidelines for Use
Your body can't use more than 1,000 mg of vitamin C in any given dose. If you need to take a larger amount, split it into two or three doses spread throughout the day.
Vitamin C can be taken with or without food, as you prefer.
When shopping for vitamin C, don't waste money on specialized products—esterified C, time-released C, vitamin C with rose hips. There's no evidence that these are more efficiently absorbed than simple ascorbic acid.
General Interaction
Large doses of vitamin C may interfere with the body's absorption of copper and selenium; be sure to get enough of these minerals (copper, about 3 mg; selenium, about 100 mcg) through food or supplements.
Cautions
Large doses of vitamin C may cause a false positive result for glucose in the urine.
If you have hemochromatosis, a genetic tendency to store excess iron (vitamin C enhances iron absorption), don't take more than 500 mg of vitamin C a day.
Vitamin C can distort the accuracy of medical tests for colon cancer and hemoglobin levels. Let your doctor know if you're taking vitamin C supplements.
Ailments Dosage
Alcoholism 1,000 mg 3 times a day
Allergies 500-1,000 mg twice a day. May be partially covered by your daily multivitamin/antioxidant.
Anemia 500 mg 3 times a day
Angina 1,000 mg daily in addition to your basic mutivitamin and antioxidant
Asthma 500-1,000 mg twice a day. May be partially covered by your daily multivitamin/antioxidant.
Athlete's Foot 1,000 mg twice a day
Burns 1,000 mg 3 times a day until healed; may be partially covered by daily multivitamin/antioxidant complex
Cancer 2,000 mg twice a day, in addition to the amount in your daily mulivitamin and antioxidant
Cataracts 500-1,500 mg once a day; all or part may be covered by your multivitamin/antioxidant
Chronic Fatigue Syndrome 500-2,000 mg 3 times a day
Colds 2,000 mg 3 times a day for 5-7 days; then reduce dose to 1,000 mg 3 times a day for the next 5-7 days
Constipation 1,000 mg twice a day. Dose may be increased by 1,000 mg a day (up to 5,000 mg a day) until bowel movements become regular. May be partially covered by daily multivitamin and antioxidant complex.
Crohn's Disease 500 mg twice a day; should be partially covered by your daily multivitamin and antioxidant.
Cuts and Scrapes 1,000 mg twice a day for 5 days.
Eczema Acute: 2,000 mg twice a day
Chronic: 1,000 twice a day; may be partially covered by your daily multivitamin and antioxidant complex.
Endometriosis 1,000 mg twice a day
Fatigue 1,000 mg twice a day
Flu 2,000 mg 3 times a day for 5-7 days; then reduce dose to 1,000 mg 3 times a day for the next 5-7 days
Gout Start with your multivitamin and antioxidant complex, then add 500 mg a day, every 5 days until you reach 1,000 mg twice a day.
Gum Disease Brush 1/2 tsp. powder along the gum line with a soft brush once every other day, alternating with vitamin E (below).
Heart Disease Prevention 750-2,000 mg daily; may be partially covered by your daily multivitamin
Hepatitis 500-1,000 mg twice a day in addition to a daily multivitamin and antioxidant complex
High Cholesterol 1,000 mg twice a day; may be partially covered by your daily multivitamin and antioxidant complex.
Infertility, Male 1,000 mg twice a day in addition to the amount in your daily vitamin program
Insect Bites and Stings 1,000 mg 3 times a day until swelling and pain are reduced.
Lupus 1,000 mg twice a day in addition to amount present in your daily multivitamin and antioxidant complex
Macular Degeneration 1,000 mg once a day in addition to that found in your daily multivitamin and antioxidant
Multiple Sclerosis 1,000 mg a day in addition to that found in your daily multivitamin and antioxidant
Nail Problems 500 mg daily; should be partially covered by a daily multivitamin/antioxidant.
Osteoporosis 250-500 mg a day
Parkinson's Disease 1,000 mg a day; may be partially covered by daily multivitamin and antioxidant.
Skin Health 1,000 mg daily; apply topically according to package instructions
Sore Throat 1,000 mg 3 times a day
Sports Injuries 1,000 mg 3 times a day for the first 5 days after an injury, then reduce to once a day as maintenance.
Sunburn 1,000 mg 3 times a day until your sunburn heals; should be partially covered by daily multivitamin and antioxidant.
Surgery Strategies 1000 mg 3 times a day until 2 to 3 weeks after surgery; then return to once a day. May be partially covered by daily multivitamin and antioxidant complex.
Thyroid Disease For hyper: 1,000 mg a day; may be partially covered by a daily multivitamin and/or antioxidant complex
Tobacco Dependence 1,000 mg 3 times a day.
Urinary Tract Infections 500 mg every other hour, as tolerated
Warts 1,000 mg 3 times a day for 10 days. Then reduce to 500 mg twice a day. A paste of powered vitamin C and water can also be applied to the wart directly.
Yeast Infection (Vaginal) 1,000 mg twice a day
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