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vitamin C





vitamin C
Also known as ascorbic acid, a water-soluble vitamin that is essential for normal growth and development. Being water-soluble means that vitamin C cannot be stored in the body, nor does the body manufacture it. Vitamin C must therefore be taken in regularly in a person's diet. Excess amounts of the vitamin leave the body through the urine.

Vitamin C is required for the growth and repair of tissues. It is necessary to form collagen, an important protein used to make skin, scar tissue, tendons, ligaments, and blood vessels. Vitamin C is essential for the healing of wounds, and for the repair and maintenance of cartilage, bones, and teeth.

Vitamin C is one of many antioxidants. Vitamin E and beta-carotene are two other well-known antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals, which are by-products that result when the body transforms food into energy. The build up of these by-products over time is largely responsible for the aging process and can contribute to the development of various health conditions such as cancer, heart disease, and a host of inflammatory conditions like arthritis. Antioxidants also help reduce the damage to the body caused by toxic chemicals and pollutants such as cigarette smoke.


Sources of vitamin C

All fruits and vegetables contain some amount of vitamin C. Foods that tend to be the highest sources of vitamin C include green peppers, citrus fruits and juices, strawberries, tomatoes, broccoli, turnip greens and other leafy greens, sweet and white potatoes, and cantaloupe.

Other excellent sources include papaya, mango, watermelon, brussels sprouts, cauliflower, cabbage, winter squash, red peppers, raspberries, blueberries, cranberries, and pineapples.


Side effects

Vitamin C toxicity is very rare, because the body cannot store the vitamin. However, amounts greater than 2,000 mg/day are not recommended because such high doses can lead to stomach upset and diarrhea.

Too little vitamin C can lead to signs and symptoms of deficiency, including:
  • Dry and splitting hair
  • Gingivitis (inflammation of the gums)
  • Bleeding gums
  • Rough, dry, scaly skin
  • Decreased wound-healing rate
  • Easy bruising
  • Nosebleeds
  • Weakened tooth enamel
  • Swollen and painful joints
  • Anemia
  • Decreased ability to fight infection
  • Possible weight gain because of slowed metabolism
A severe form of vitamin C deficiency is known as scurvy, which mainly affects older, malnourished adults.


Related category

   • BIOCHEMISTRY

Source: U.S. National Library of Medicine