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Vitamin C, also known as ascorbic acid, is a water soluble, crystalline vitamin, found in citrus fruits, cruciferous vegetables, leafy greens, peppers and strawberries. Besides being an essential element in the diet of humans it is also important for many other animals. It has been used to remedy deficiencies to prevent and treat upper respiratory conditions, easy bruising, reflex sympathetic dystrophy, high blood pressure, bedsores and skin aging. But an excess of ascorbic acid may cause a burning sensation during urination, diarrhea, skin rash, nausea and may disturb the absorption and metabolism of cyanocobalamin.
Vitamin C and skin care:
Vitamin C is one of the most important ingredients for your skin. Vitamin C and skin care are interrelated. So many new products are coming into the market that we become confused before making a definite choice between the hi-tech and the most practical cure to skin problems.
The basic goal of any skin care product is to provide you a younger and fresh look everyday. It aims at rejuvenating your skin maintaining its earlier glow and health. Vitamin C does the same in a number of ways:
Moisturizes
Encourages growth of collagen
Softens
Exfoliates and cleanses
Removes wrinkles
Research reveals that, Vitamin C is the only thing that stimulates the growth of collagen that provides structure and strength to your skin. The production of collagen decreases with age and reveals wrinkles on the skin. But it is possible to reverse the process, at least for a while, by stimulating the production of collagen.
Role as an antioxidant:
An antioxidant is a molecule which is able to slow down or prevent the oxidation of other molecules. Vitamin C serves the purpose of an antioxidant when put on skin and thus makes it the ideal element for skin. But Vitamin C does not provide sun protection. It protects your skin cells against the effects of the free radicals which are the by-products that are produced when our bodies transform food into energy. These free radicals can cause a real harm to your skin when they are exposed to the ultra violate rays of the sun, accelerate aging, cause heart disease, and a number of inflammatory conditions like arthritis and can even cause skin cancer. Antioxidants also help reduce the ill effects of the toxic chemicals and pollutants such as cigarette smokes on our body.
Our body can not manufacture vitamin C on its own, nor does it store it. It is therefore necessary to include plenty of vitamin C-containing foods in your daily diet.
Other Functions:
Vitamin C helps in the synthesis of the Neurotransmitter, neropinephrine. Neurotransmitters are critical to brain function and can also affect the mood. Addition to this, Vitamin C is required for the synthesis of Carnitine, a small molecule necessary for the transport of fat into cellular organelles known as Mitochondria, where the fat is transformed into energy. Vitamin C also involves in the metabolism of cholesterol to bile acids, which may have signs of blood cholesterol levels and the incidence of gallstones.
Deficiency:
The deficiency of Vitamin C has been known for many centuries as the potentially fatal diseases. Its deficiency may cause Scurvy and poor wound repair.
Scurvy:
Bleeding and bruising, hair and tooth loss, and joint pain and swelling are some of the symptoms of scurvy. Weakening of blood vessels, connective tissue, and bone, which all contain collagen, give rise to these symptoms. Scurvy is rare in developed countries because it needs 10 mg of vitamin C daily to prevent this disease.
Cardiovascular diseases:
Research reveals that low or deficient intakes of vitamin C are associated with an increased risk of cardiovascular diseases. A modest dietary intake of about 100 mg/day ware sufficient for to minimize the risks of cardiovascular disease among nonsmoking men and women.
Stroke:
Extensive Study reveals that more than 2,000 residents of a rural Japanese community for 20 years are more prone to have stroke. The risks increase in those who have the highest serum levels of vitamin C, 29% lower than in those with the lowest serum levels of vitamin C.
It was seen that the risk of stroke was 54% lower in those who consumed vegetables 6-7 days of the week than in those who consumed vegetables 0-2 days of the week. In this population, serum levels of vitamin C depended highly on fruit and vegetable intake. Therefore, it is difficult to separate the effect of Vitamin C and other components of fruit and vegetables to decrease the risk factors.
A prospective study on 870 men over a period of 25 years found that those who consumed more than 83 mg of vitamin C daily had 64% reduction in lung cancer compared to those who consumed less than 63 mg per day.
Cataracts:
Visual impairment as a result of cataracts is the most common problem throughout the world. In the U.S., cataract-related expenditures are estimated to exceed $3 billion annually. Cataracts occur more frequent and severe as people age. Deficiency of vitamin C in the lens of the eye is associated with increased severity of cataracts in humans. Some studies have observed, considerable intake of vitamin C, and increased blood levels of vitamin C can decrease the risk of cataracts.
Gout:
Gout can be defined as abnormally high blood levels of uric acid (urate). Urate crystals may form in joints and cause inflammation and pain. It may also affect the kidneys and urinary tract, resulting in kidney stones. The tendency to develop abnormally high blood levels of uric acid and gout is often hereditary; however, dietary and lifestyle modification may be help to prevent and provide remedy to gout. More recently, a prospective study on 46,994 men for 20 years found that total daily vitamin C intake was inversely proportionate to the risk associated with gout, which means, higher intakes of Vitamin C indicates greater risk reductions. The results of this study also reveal that supplemental vitamin C may be help to prevent the gout.
Osteoarthritis:
Vitamin C is essential for the body to produce collagen, which is a part of normal cartilage. Cartilage is destroyed in osteoarthritis (OA), putting pressure on bones and joints. According to some researchers, free radicals, molecules produced by the body that can damage cells and DNA, may also be involved in the destruction of cartilage. Antioxidants such as vitamin C decelerate the damage caused by free radicals. However, no strong evidence is found that assures that taking vitamin C supplements will help treat or prevent OA. But the evidence only suggests that people who eat diets rich in vitamin C are less likely to be diagnosed with arthritis.
Taking nonsteroidal, anti-inflammatory drugs can decrease the levels of vitamin C. If you take these drugs regularly for OA, you might need to take a vitamin C supplement.
Common Cold:
It is a common believe among people that a good intake of Vitamin C is a cure to common cold. But the scientific evidence doesn\’t support this view. Taking vitamin C supplements regularly (not just at the beginning of a cold) only reduces the duration of cold for a very short period (about 1 day). The only other piece of evidence supporting vitamin C as a possible prevention to colds comes from studies examining people exercising in extreme environments (athletes such as skiers and marathon runners, and soldiers in the Arctic). In these studies, vitamin C did seem to cut down the risk of getting a cold.
Cancer:
Research on groups of people over time suggest that a considerable intake of vitamin C may lower the rates of cancer, including skin cancer, cervical dysplasia (changes to the cervix which may be cancerous or precancerous, picked up by pap smear), and, possibly, breast cancer. As these foods also contain many other beneficial nutrients and antioxidants, apart from vitamin C, it\’s impossible to say for certain that vitamin C is protects against cancer. Taking vitamin C supplements does not help much.
It can’t be said that taking large doses of vitamin C once diagnosed with cancer will help your treatment. Moreover, some doctors are concerned about the facts that large doses of antioxidants from supplements could interfere with chemotherapy medications. If you are undergoing chemotherapy, consult your doctor before taking vitamin C or any supplement.
Age-related Macular Degeneration:
Vitamin C (500 mg) works with other antioxidants, including zinc (80 mg), beta-carotene (15 mg), and vitamin E (400 IU) to protect the eyes against developing macular degeneration (AMD). This is the leading cause of legal blindness in people over 55 in the United States. The people with advanced AMD seem to benefit. It isn\’t known whether this combination of nutrients helps prevent AMD or is beneficial for people with less advanced AMD.
Pre-eclampsia:
It is said that taking vitamin C along with vitamin E may help prevent pre-eclampsia in women who are at high risk. Its symptom includes high blood pressure and too much protein in the urine. Pre-eclampsia is a common cause of pre-term births. But this is not supported by all the studies done so far.
Asthma:
When it comes to discuss whether lack of Vitamin C may cause asthma, the reactions are mixed. However some cases of asthma show that low levels of ascorbic acid or Vitamin C are more common in asthma patients. Therefore some researchers feel that poor intake of Vitamin C might increase the risk of asthma. Other studies reveal that Vitamin C may help reduce symptoms of exercise-induced asthma.
Diabetes Mellitus:
People with diabetes are more likely to succumb due to cardiovascular diseases (heart disease and stroke).
Diabetes is a condition of increased oxidative stress. Higher intakes of antioxidant nutrients are capable of decreasing cardiovascular disease risk in diabetic individuals. In support of this hypothesis, a 16-year study of 85,000 women, 2% of whom were diabetic, found that vitamin C supplement use (400 mg/day or more) significantly reduce the risk of fatal and nonfatal coronary heart disease in the entire cohort as well as in those with diabetes. In contrast, a 15-year study of postmenopausal women found that diabetic women, taking at least 300 mg/day of vitamin C from supplements when the study began were at the verge of higher risk of death from coronary heart disease and stroke than those who did not take vitamin C supplements
Protection against Other diseases:
Vitamin C may also provide protection against following diseases. But this needs further accurate studies:
- Boosting immune system function
- Maintaining healthy gums
- Improving vision for those with uveitis (an inflammation of the middle part of the eye)
- Treating allergy-related conditions, such as asthma, eczema, and hay fever (called allergic rhinitis)
- Reducing effects of sun exposure, such as sunburn or redness (called erythema)
- Alleviating dry mouth, particularly from antidepressant medications (a common side effect from these drugs)
- Healing burns and wounds
- Decreasing blood sugar in people with diabetes
- Reducing hypertension.
Dietary Sources:
Some definite sources of vitamin C include: oranges, green peppers, sweet bell peppers, watermelon, papaya, grapefruit, cantaloupe, strawberries, kiwi, mango, broccoli, tomatoes, Brussels sprouts, collards, cauliflower, cabbage, and citrus juices or juices fortified with vitamin C. Raw and cooked leafy greens (turnip greens, spinach, parsley), red and green peppers, canned and fresh tomatoes, potatoes, winter squash, raspberries, blueberries, cranberries, and pineapple are also enriched with vitamin C.
Vitamin C is a highly sensitive substance to air, water, and temperature. Cooking, storage and processing may decrease its nutritional value. About 25% of the nutritional value of vitamin C in vegetables can be lost simply by blanching (boiling or steaming the food for a few minutes). This also occurs in the freezing and unthawing of vegetables and fruits rich with Vitamin C. Cooking of vegetables and fruits for a long time (about 10-20 minutes) can destroy over one half the Vitamin C content. When fruits and vegetables are canned and then reheated, only 1/3 of the original vitamin C content is left. Therefore, the best possible way to gain maximum nutritional value from Vitamin C is the consumption of fresh and raw vitamin C-rich foods.
Other Available Forms:
Natural or synthetic vitamin C, also called ascorbic acid, is available in a variety of forms such as tablets, capsules, and chewable. But vitamin C is also available in powdered crystalline, effervescent, and liquid forms. Vitamin C can also be purchased in dosages ranging from 25 – 1,000 mg.
If you find that regular ascorbic acid upsets your stomach you can go for the “Buffered” Vitamin C. An esterified vitamin C is also available in the market. This is mild on the stomach especially for those who are prone to heartburn.
Metabolite complex form of vitamin C {sold commercially under the trade name Ester-C(TM)}, in which ascorbic acid is combined with several of its naturally occurring metabolites including dehydroascorbate, threonate, and aldonic acids are highly available.
Daily intake of dietary vitamin C (according to U.S. recommended dietary allowances), considering pediatric and adult is listed below:
In Case Of Pediatric to adolescence
- Infants 6 – 12 months50mg
- Children 1 – 3 years15mg
- Children 4 – 8 years25mg
- Children 9 – 13 years45mg
- Adolescent girls 14 – 18 years65mg
- Adolescent boys 14 – 18 years75mg
| Age Group | Prescribed Quantity |
|---|---|
| Birth – 6 months | 40 mg |
In Case Of Adult:
Women over 18 years75mg
Breastfeeding women120mg
| Age Group | Prescribed Quantity |
|---|---|
| Men over 18 years | 90mg |
Precautions:
You should consult your health care provider before you take dietary supplements because it may give rise to some side effects or interact with medications.
Vitamin C supplements have a diuretic effect, so it is necessary to drink plenty of fluids when taking them.
Most commercial vitamin C is derived from corn. But people sensitive to corn are advised to look for alternative sources, such as sago palm.
Vitamin C increases the amount of iron absorbed from foods. People with hemochromatosis (an inherited condition where too much iron builds up in the body), therefore, should avoid taking take vitamin C supplements.
Vitamin C is considered safe because your body gets rid of what it does not use, but if the doses are high (more than 2,000 mg daily), it can cause diarrhea, gas, or stomach upset. If these side effects occur, you may lower the dose of vitamin C.
People with kidney problems should consult their physician before taking vitamin C.
People who smoke or use nicotine patches need to take more vitamin C rich fruit and vegetables because nicotine cuts down the effect of vitamin C in the body.
Infants born to mothers taking 6,000 mg or more of vitamin C may develop rebound scurvy. This happens as their intake of vitamin C drops after birth. If you are pregnant, discuss with your doctor before taking more than 1,000 mg of vitamin C.
Drug-Nutrient Interactions:
Some drugs can diminish the body\’s supply of vitamin C. The list includes; oral contraceptives (birth control pills), NSAIDs (non-steroidal anti-inflammatory drugs including aspirin), corticosteroids (like cortisone), sulfa drugs (often used as antibiotics or in cancer treatment), and barbituates.