• Is too much vitamin C harmful?

vitamin C supplements on a spoon, with oranges, citrus fruits in background

Your body needs vitamin C, but megadoses can cause many digestive problems. Find out how much of the nutrient you really require.

While vitamin C (ascorbic acid) is an essential nutrient, it's possible to have too much of it.

Vitamin C is a water-soluble vitamin that supports normal growth and development and helps your body absorb iron. Because your body doesn't produce or store vitamin C, it's important to include vitamin C in your diet. For most people, an orange or a cup of strawberries, chopped red pepper, or broccoli provides enough vitamin C for the day.

For adults, the recommended daily amount for vitamin C is 65 to 90 milligrams (mg) a day, and the upper limit is 2,000 mg a day. Although too much dietary vitamin C is unlikely to be harmful, megadoses of vitamin C supplements might cause:

  • Diarrhea
  • Nausea
  • Vomiting
  • Heartburn
  • Abdominal cramps
  • Headache
  • Insomnia

Remember, for most people, a healthy diet provides an adequate amount of vitamin C.

This article is written by Katherine Zeratsky, R.D., L.D.  and Mayo Clinic Staff. Find more health and medical information on mayoclinic.org..

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