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Alternative Names Return to top
Ascorbic acidDefinition Return to top
Vitamin C is a water-soluble vitamin that is necessary for normal growth and development.
Water-soluble vitamins dissolve in water. The body cannot store them. Leftover amounts of the vitamin leave the body through the urine. That means you need a continuous supply of such vitamins in your diet.
Function Return to top
Vitamin C is required for the growth and repair of tissues in all parts of your body. 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 our bodies transform 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.
The body does not manufacture vitamin C on its own, nor does it store it. It is therefore important to include plenty of vitamin C-containing foods in your daily diet.
Food Sources Return to top
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 Return to top
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:
A severe form of vitamin C deficiency is known as scurvy, which mainly affects older, malnourished adults.
Recommendations Return to top
The best way to get the daily requirement of essential vitamins, including vitamin C, is to eat a balanced diet that contains a variety of foods from the food guide pyramid.
Vitamin C should be consumed every day because it is not fat-soluble and, therefore, cannot be stored for later use.
The Food and Nutrition Board at the Institute of Medicine recommends the following amounts of vitamin C:
Infants and Children
Adolescents
Adults
Women who are pregnant or breastfeeding and those who smoke need higher amounts. Ask your doctor what is best for you.
References Return to top
Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. December 2008:35(4);729-747.
Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.
Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 237.
Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. National Academy Press, Washington, DC, 2000.
Update Date: 3/7/2009 Updated by: Linda Vorvick, MD, Family Physician, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.