What is vitamin C?

Elizabeth Casparro, MPH,RD
Nutrition & Dietetics

Vitamin C is a water-soluble vitamin that is found in two main forms: ascorbic acid and dehydroascorbic acid. Since it is water-soluble, excess amounts are easily excreted from the body and it is more difficult to build up to toxic levels. However, there is an Upper Limit (aka toxic level), which is 2 grams per day which has been shown to cause gastrointestinal symptoms such as diarrhea and bloating. The Recommended Daily Allowance (RDA) for women is 75 mg per day and 90 mg per day for men.

Vitamin C has many different functions and food sources. First, it is necessary for collagen development. Second, it aids with iron absorption. Third, it works as an antioxidant, which neutralizes free radicals and thereby reducing damage to our cells. Food sources include all citrus fruits, strawberries, kiwi, tomatoes, broccoli, red bell pepper and many more.

Vitamin C, also known as ascorbic acid, is a vitamin that occurs naturally in many foods like fruits and vegetables. Vitamin C helps with the development of bones and connective tissue and helps the body with iron absorption. Vitamin C tablets can be used as a supplement to treat people who have low levels of vitamin C or to treat or prevent scurvy.

Vitamin C also known as ascorbic acid, acts as a coenzyme that is needed to synthesize and use certain amino acids. In particular, vitamin C is needed to make collagen, the most abundant protein in your body. Collagen is plentiful in your connective tissue, which supports and connects all your body parts, so this protein is needed for healthy bones, teeth, skin, and blood vessels. Thus, a vitamin C deficient diet would affect your entire body.

Because vitamin C is a water soluble vitamin, it isn't store in your body so you need to make sure that your diet is adequate in vitamin C daily. Good sources include:

  • citrus fruits
  • strawberries,
  • peppers
  • broccoli
  • tomatoes


Picture of oranges

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.