JAMA PATIENT PAGE The Journal of the American Medical Association
How much vitamin C do you need?
itamin C has become popular WHAT IS VITAMIN C?
because of its role as an
Vitamin C (also known as ascorbic acid) is
antioxidant, which potentially 1 of 13 major vitamins, which are a group
offers protection from some diseases of complex chemicals that your body needs
and degenerative aspects of aging. But to function properly. It is 1 of the water-
there can be too much of a good thing. soluble vitamins, which means that your
Taking too much vitamin C can cause body uses what it needs and eliminates the
side effects such as nausea and excess out of the body.
How much is enough may be a What foods HOW MUCH DO YOU NEED?
difficult question to answer. The Food contain The current RDA for vitamin C for most
and Nutrition Board of the National vitamin C? people 15 years old and older is 60 mg
Academy of Sciences is revising its daily. Among those who need more
vitamin C include pregnant women (70
current recommendations for mg), breast-feeding women (90 to 95
vitamin C intake. In the April 21, mg), and smokers (at least 100 mg).
1999, issue of JAMA, experts at the Because vitamin C can’t be stored in the
National Institutes of Health Strawberries (1 cup, sliced) 95 mg body, it is important to replenish it by
suggest that the current recommended Papaya (1 cup, cubes) 85 taking the recommended amounts of
dietary allowance (RDA) of vitamin C vitamin C each day.
Kiwi (1 medium) 75
should be increased from 60 mg to Orange (1 medium) 70 IS MORE BETTER?
100-200 mg daily. They emphasize Orange juice (1/2 cup) 50
that whenever possible, the vitamin C Some people take large amounts of
Cantaloupe (1/4 medium) 60 vitamin supplements because of the
should come from fruits and vegetables, Mango (1 cup, sliced) 45 belief that these supplements improve
and that people can get the
Grapefruit (1/2 medium) 40 health or that they can ward off certain
recommended amount by eating 5 illnesses, such as colds. But there is no
Grapefruit juice (1/2 cup) 35
servings of fruits and vegetables daily. convincing evidence to show that this is
Pepper, red or green (1/2 cup)
Vitamin C is found in foods such as true. Taking excessive amounts of
Raw 65 vitamin C (more than about 1000 mg
citrus fruits, tomatoes, strawberries, bell
peppers, and broccoli. Eating well- Cooked 50 per day) may cause nausea, stomach
balanced meals and foods rich in Broccoli (1/2 cup, cooked) 60 cramps, diarrhea, and possibly kidney
Kale (1 cup, cooked) 55 stones. Discuss the use of vitamin
vitamin C is the best way to get your supplements with your doctor.
required intake. A diet rich in fruits Brussels sprouts (1/2 cup, cooked) 50
and vegetables may also be beneficial in Snow peas (1/2 cup, cooked) FOR MORE INFORMATION:
helping to prevent some types of Fresh 40
• American Dietetic Association
cancer. Frozen 20 Consumer Nutrition Hot Line
Potato (1 medium, baked) 25 800/366-1655 or www.eatright.org
Source: U.S. Department of Agriculture • Mayo Clinic Health Oasis
WHAT DOES IT DO? www.mayohealth.org
Vitamin C helps body cells grow and stay healthy, including those in bones, teeth, gums,
ligaments, and blood vessels. It also helps the body’s response to infection and stress, and INFORM YOURSELF:
helps use iron efficiently. If your body doesn’t get enough daily vitamin C, you’re more To find this and previous JAMA Patient
likely to have skin bruising, bleeding gums, poor healing of wounds, loosening of teeth, Pages, check out the AMA’s Web site at
tender joints, and infections. www.ama-assn.org/consumer.htm.
Additional Sources: American Dietetic Association, AMA’s Family Medical Guide, AMA’s Encyclopedia of
Mi Young Hwang, Writer The JAMA Patient Page is a public service of JAMA and the AMA. The information and recommendations appearing
on this page are appropriate in most instances; but they are not a substitute for medical diagnosis. For specific
Richard M. Glass, MD, Editor information concerning your personal medical condition, JAMA and AMA suggest that you consult your physician.
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1460 JAMA, April 21, 1999—Vol 281, No. 15
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