Vitamin C - ascorbic acid - information
Vitamin C is also known as, ascorbic acid, L-ascorbic acid, dehydroascorbic acid, the antiscorbutic vitamin, L-xyloascorbic acid and L-threo-hex-2-uronic acidy-lactone, is a much talked about vitamin, with people claiming it as a cure-all for many diseases and problems - from cancer to the common cold. Yet, this miracle vitamin cannot be manufactured by the body, and needs to be ingested.
Vitamin C is required in the synthesis of collagen in connective tissue, neurotransmitters, steroid hormones, carnitine, conversion of cholesterol to bile acids and enhances iron bioavailability. Ascorbic acid is a great antioxidant and helps protect the body against pollutants.
Ascorbic acid also promotes healthy cell development, proper calcium absorption, normal tissue growth and repair - such as healing of wounds and burns. It assists in the prevention of blood clotting and bruising, and strengthening the walls of the capillaries.
Vitamin C is needed for healthy gums, to help protect against infection, and assisting with clearing up infections and is thought to enhance the immune system and help reduce cholesterol levels, high blood pressure and preventing arteriosclerosis.
When there is a shortage of Vitamin C, various problems can arise, although scurvy is the only disease clinically treated with vitamin C. However, a shortage of vitamin C may result in "pinpoint" hemorrhages under the skin and a tendency to bruise easily, poor wound healing, soft and spongy bleeding gums and loose teeth.
Edema (water retention) also happens with a shortage of vitamin C, and weakness, a lack of energy, poor digestion, painful joints and bronchial infection and colds are also indicative of an under-supply.
The dosage underneath is the Recommended Dietary Allowance (RDA), but be aware that this dosage is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the toxicity level must be kept in mind.
The RDA is 60 mg, per day - yet this amount will only prevent you from picking up scurvy and more recent studies suggest that an intake between 200 - 500 mg per day may be the most beneficial for healthy people.
The recommend dosage for pregnant or lactating women is 75-95 mg per day.
Since ascorbic acid is a water-soluble vitamin, toxic levels are not built up or stored in the body, and any excess is lost mostly through urine. If extremely large amounts are taken gastrointestinal problems may appear, but will normalize when the intake is cut or reduced.
To determine a level where a person might experience discomfort is difficult, since some people can easily stomach up to 25,000 mg per day, while others start having a problem at 600 or 1,000 mg.
Some people using mega dose therapy of vitamin C may have side effects such as gastrointestinal complaints including diarrhea, nausea and abdominal cramps. These side effects normally stop as soon as high potency intake is reduced or stopped.
Mega doses of vitamin C should be avoided in individuals with a history of renal stones (kidney stones) due to oxalate formation or hemochromatosis or other diseases related to excessive iron accumulation.
Extremely high dosage of vitamin C may predispose premature infants to hemolytic anemia due to the fragility of their red blood cells.
Vitamin C will be more effective if taken with bioflavonoids, calcium and magnesium. To enhance the antioxidant properties, it will be best to take it with the other anti-oxidants, as there is strong evidence of synergy between all of them.
The need for vitamin C will dramatically increase in times when the body is subjected to trauma, infections, and strenuous exercise, elevated environmental temperatures or if the person is a cigarette smoker. Cigarette smokers should supplement with a minimum additional 100 mg per day.
Antagonists that destroy this vitamin are air, heat, water as well as prolonged storage, overcooking and processing.
Antacids, alcohol, antidepressants, birth control pills and steroids will also deplete this vitamin.
Good sources of vitamin C are green leafy vegetables, berries, citrus fruits, guavas, tomatoes, melons, papayas etc.
Ongoing research is looking at the clinical use of vitamin C in the prevention and treatment of human diseases.
In 1976 an article co-authored by Linus Pauling described that 100 terminal cancer patients treated with intravenous vitamin C, followed by oral maintenance, lived four times longer than a control group of 1,000 patients who did not receive vitamin C.
This article has been hotly disputed for decades, and the Mayo clinic did studies to prove the opposite - but none the less, vitamin C remains an important vitamin.
Yet, the fact remains that Linus Pauling is the first person to win two unshared Nobel prizes - one for chemistry and the other for peace.
However in 2009 Grober assessed that high dose intravenous vitamin C therapy may have benefits in patients with advanced cancers, and cancers with poor prognosis and limited therapeutic options, but that further clinical studies regarding the safety and efficacy of this vitamin C therapy were necessary.
Humans cannot synthesize ascorbic acid due to lack of an enzyme gulonolactone oxidase and must be taken as part of their diet daily, as it is depleted by killing of free radicals, and excesses as excreted in the urine.
Although Paul Linus and Adelle Davis both stated very clearly that they believed in the wonderful properties of vitamin C – both were criticized, with a lot of the criticism having had to be retracted due to new medical research.
Two dioxygenases involved in the biosynthesis of carnitine also require vitamin C as a cofactor for maximal activity. Carnitine is essential for the transport of activated long-chain fatty acids into the mitochondria; as a result, vitamin C deficiency results in fatigue and lethargy, early symptoms of scurvy and a general sense of feeling un-wellness.
In a test vitamin C's antioxidant capacity was tested and the ability to protect the cell DNA (The DNA [Deoxyribonucleic acid] contains the genetic instructions (genes, genomes, telomeres, centromeres, pseudogenes etc) used in the development and functioning of the cells and the body in total) from strand breaks and it was found that in people with a lower vitamin C level had increased DNA strand breaks when the cells were challenged with hydrogen peroxide (H(2)O(2)).
It acts as a reductor (redox) agent required for synthesis of collagen fibers through hydroxylation of proline and lysine.
In endothelial cells, vitamin C helps to prevent endothelial dysfunction, stimulates type IV collagen synthesis, and enhances cell proliferation and in the vascular (heart) smooth muscle cells, it inhibits dedifferentiation, recruitment, and proliferation in areas of vascular damage.
In macrophages (white blood cells that fight disease in our bodies), ascorbate decreases oxidant stress related to their activation, decreases uptake and degradation of oxidized LDL in some studies, and enhances several aspects of their function, and it also seems to be of value in the early stages of atherosclerosis (artery wall thickening as the result of a build-up of fatty materials such as cholesterol).
Vitamin C, a water-soluble antioxidant in plasma, stimulates and protects collagen synthesis while recycling vitamin E.
Plasma C-reactive protein (CRP) is an inflammatory marker that predicts cardiovascular disease, and a study found that vitamin C significantly reduced CRP among individuals with CRP and may prove interesting to follow-up on possibilities of vitamin C helping with health problems related to obesity and overweight.
Ascorbic acid (vitamin C) can also help in reducing bruising and vitamin C supplements of </=2000 mg/d are safe for most adults.
Ascorbate (vitamin C) is a vital antioxidant molecule in the brain and ascorbate is proposed as a neuromodulator of glutamatergic, dopaminergic, cholinergic, and GABAergic transmission and related behaviors.
Neurodegenerative diseases typically involve high levels of oxidative stress and thus vitamin C has been shown to have potential therapeutic roles against ischemic stroke, Alzheimer's disease, Parkinson's disease, and Huntington's disease.
Tissue mercury levels in humans have increased during the past 50 years to an alarming concentration, with possible deleterious effects that may involve neurological, cardiovascular, and immunological pathology.
In a study glutathione and high-dose vitamin C for treatment of high-level mercury showed that an average of 69% reduction of urine mercury by provocation analysis.
It has long been suspected that ascorbic acid is involved in many cellular reactions it has become clear that in animal cells the ascorbate does not seem to be directly involved in catalytic cycles. Rather its major function seems to keep prosthetic metal ions in their reduced form.
The role of ascorbate (vitamin C) as a reductant (redox effect) in these enzymatic reactions complements its other antioxidant functions which have been recently appreciated, including that as a scavenger of free radicals.
Therefore, it seems that the major function of ascorbate is to protect tissues from harmful oxidative products and to keep certain enzymes in their required reduced forms. However, it remains unclear how the deficiency of ascorbate leads to the pathological symptoms found in scurvy.
In a study daily dosages of 500 to 3,000 mg. were taken, which is roughly 8 to 50 times the RDA of 60 mg., to subjects recovering from surgery, other injuries, decubital ulcers, and leg ulcers induced by hemolytic anemia and all showed a positive effect from the vitamin C intake.
Four grams (4,000 mg) of ascorbic acid daily produced a significant improvement in the quality of newly synthesized collagen but did not alter that formed prior to the supplementation of C. The combined evidence in this review provides a substantial base for further research, both clinical and experimental trials, concerning the interrelationships between vitamin C and the body's healing potential.
Ascorbic acid was shown to have anti-inflammatory and healing effects, guaranteeing a suitable environment and conditions for faster skin repair.
Higher intakes of vitamin C and linoleic acid and lower intakes of fats and carbohydrates are associated with better skin-aging appearance.
Promoting healthy dietary behaviors and higher intake of vitamin C may have additional benefit for skin appearance in addition to other health outcomes in the population.
In the analysis of micronutrients, higher intakes of vitamins C and E from foods were each associated with longer telomeres, (A telomere is a region of repetitive DNA at the end of a chromosome, which protects the end of the chromosome from deterioration) even after adjustment for multivitamin use.
Furthermore, intakes of both nutrients were associated with telomere length among women who did not take multivitamins.
Applications of some drugs (antioxidants--asiaticoside, vitamin E and ascorbic acid; calcium D-pantothenate, exogenous fibronectin; antileprosy drugs--oil of hydnocarpus; alcoholic extract of yeast) have shown to accelerate wound healing.
Werner Syndrome (WS) is a premature aging disorder caused by mutations in a RecQ-like DNA helicase. In a study the results indicate that vitamin C supplementation could be beneficial for patients with Werner Syndrome.
Recent literature clearly shows that vitamin C and B affect bone quality by determinant "collagen cross-link formation".
In a study about bone health in older males, the associations were attenuated but retained borderline significance (P-trend < 0.1) after adjusting for potassium intake (a marker of fruit and vegetable intake), suggesting that vitamin C effects may not be separated from other protective factors in fruit and vegetables. Null associations were observed among women. These results suggest a possible protective role of vitamin C for bone health in older men.
Higher intakes of vitamin C or the combined intake of antioxidants had long-term protective associations against development of nuclear cataract in this older population, and a study showed that there was a clear relationship between ascorbic acid (vitamin C) and the occurrence of cataracts.