Vitamin C

The A-B-C's of Vitamin Supplements

Peer Reviewed

capsules filled with orangesVitamin C is also known as ascorbic acid. It is an antioxidant essential for tissue growth and repair. The body cannot produce vitamin C, and since it is water-soluble and not stored, it must be obtained from food and supplements.

Ascorbic acid is necessary to produce collagen; a protein needed to make tendons, ligaments, blood vessels, and skin. It may help to heal wounds, repair cartilage, mend bones, and aid the body in absorbing iron. Vitamin C may help to prevent certain types of cancer.

Additionally, vitamin C may aid in adrenal gland function (antistress hormone production), protect against the effects of pollution (used by the liver to help detoxify the body), increase good cholesterol (high-density lipoprotein), and lower blood pressure.

There is conflicting evidence about vitamin C’s ability to prevent colds.

Dosage Guidelines
Consider the guidelines below to make sure an adequate amount of vitamin C is consumed each day.
Vitamin C Table

Sources of Vitamin C
Some of the best food sources include orange juice, grapefruit, strawberries, papaya, cantaloupe, green peppers, leafy green vegetables, broccoli, and tomatoes. Eating fresh fruits and vegetables insures the highest vitamin C content.

Vitamin C comes in many forms: capsules, tablets (chewable, effervescent), powdered crystalline, and liquid. Dosages range from 25 mg to 1,000 mg. Ascorbic acid is also available buffered to protect the stomach.

Although vitamin C is basically non-toxic, high doses (in excess of 2,000 mg daily) may cause diarrhea and stomach discomfort.

  • If prescription medication is taken on a regular basis, and before exceeding the recommended daily allowance, consult with a medical professional.
  • Certain prescription medications taken to treat diabetes medications and sulfa drugs may not be as effective if taken with vitamin C.
  • Aspirin and vitamin C taken together in large doses may result in stomach irritation.
  • Vitamin C increases the absorption of iron in food and supplement forms.
  • Vitamin C interferes with the copper absorption.


Disclaimer: Many people report feeling improvement in their condition and/or general well-being taking dietary, vitamin, mineral, and/or herbal supplements. The Editorial Board of, however, cannot endorse such products since most lack peer-reviewed scientific validation of their claims. In most cases an appropriate diet and a "multiple vitamin" will provide the necessary dietary supplements for most individuals. Prior to taking additional dietary, vitamin, mineral, and/or herbal supplements it is recommended that patients consult with their personal physician to discuss their specific supplement requirements.

Updated on: 03/09/16
Continue Reading
Osteoporosis: Vitamin C and Keeping Healthy
Thomas G. Lowe, MD
While some patients have reported improvement after taking this supplement, the Editorial Board is unable to endorse the supplement due to the lack of peer reviewed scientific literature indicating its efficacy for treating spinal conditions. Patients should consult their physician before starting a supplement program.
Continue Reading:

Osteoporosis: Vitamin C and Keeping Healthy

Vitamin C has recently been recognized as having an important role in the prevention of osteoporosis because of its ability to increase bone density.
Read More