Vitamin C
Vitamin C, or L-ascorbic acid, is an essential nutrient for humans, as well as other species of primates, birds and fish. Unlike other organisms, humans do not make Vitamin C internally. Vitamin C is water-soluble, and is not stored by the body.
What is the function of Vitamin C?
Vitamin C is necessary for tissue growth and repair, for the formation of collagen (a protein used to make skin, scar tissue, ligaments and blood vessels) and for keeping bones and teeth healthy.
What foods are good sources of Vitamin C?
All fruits and vegetables contain at least some Vitamin C. The best sources include green and red peppers, citrus fruits, tomatoes, leafy greens, sweet and white potatoes, blueberries, cranberries and Brussels sprouts.
What is the recommended daily intake of Vitamin C?
Vitamin C should be consumed every day, because it cannot be stored for future use. The Recommended Dietary Allowance for men ages 19 and older is 45 milligrams/day. For women ages 19 and older, it is 75 mg/day.
What is Vitamin C deficiency?
The best known Vitamin C deficiency disease is scurvy, rarely seen in developed countries, because so little Vitamin C is needed to prevent its occurrence. Cases have been seen in the last few years in the very young and very old, and those on restricted diets. The deficiency is characterized by chronic bleeding and bruising, hair and tooth loss, and pain and swelling of the joints.
What about Vitamin C supplements?
Natural and synthetic Vitamin C supplements are available, and they are chemically identical; there is no advantage to using one over the other.
How much Vitamin C is toxic?
Toxicity from high doses of Vitamin C, either in food or supplement form, is rare. The symptoms include kidney stones, diarrhea, nausea, vomiting, faintness, dizziness and tooth erosion (from chronic chewing on Vitamin C tablets). A Tolerable Upper Intake Level for Vitamin C is 2,000 mg/day for adults age 19 and older.
What about Vitamin C and drug interactions ?
High doses of Vitamin C, in dietary or supplement form, should be avoided by anyone with a condition aggravated by high levels of acid, such as gout or cirrhosis, or anyone with kidney failure. Vitamin C may increase the adverse affects of aspirin. The effect of Vitamin C may be decreased by some antibiotics, oral estrogens, blood thinners and barbiturates.
What are the benefits of Vitamin C?
Preliminary studies are ongoing to find valid therapeutic uses for Vitamin C to treat and prevent several chronic conditions: heart disease, ulcers, stroke, cancer, high blood pressure, diabetes, asthma and the common cold. Current test results are unclear as to the valid scientific evidence for or against the use of Vitamin C for these conditions. The studies follow large numbers of people for long periods of time, and scientific testing will continue before any final conclusions are determined.
