Nutrition 101: Vitamin C

Vitamin C, also known as ascorbic acid, is a water-soluble vitamin, meaning that your body doesn’t store it. It is found in high amounts in many fruits and vegetables. Scurvy (Vitamin C deficiency) was first discovered in British sailors who were not consuming many foods that contained Vitamin C. From then on they carried Vitamin C–packed limes on their voyages.

Recommended Intakes

The Dietary Reference Intakes (DRI) for Vitamin C are shown below:

Age Group	Recommended Dietary Allowance (RDA) per Day	Tolerable Upper Intake Level (UL) per Day
Adults
19 years and up	90 mg male75 mg female	2,000 mg
Kids and Youth
1 to 3 years	15 mg	400 mg
4 to 8 years	25 mg	650 mg
9 to 13 years	45 mg	1,200 mg
14 to 18 years	75 mg male65 mg female	1,800 mg
Special Considerations
Pregnant women 14 to 18 years	80 mg	1,800 mg
Pregnant women 19 years and up	85 mg	2,000 mg
Lactating women 14 to 18 years	115 mg	1,800 mg
Lactating women 19 years and up	120 mg	2,000 mg

People who smoke and those who are exposed to secondhand smoke need 35 mg more Vitamin C per day than nonsmokers. Cigarette smoke increases the amount of Vitamin C that the body needs to repair damage caused by free radicals.

What Does Vitami​n C Do?

Vitamin C has a very important protective effect on the body. Like many other plant-based nutrients, including Vitamin E and beta-carotene, Vitamin C is an antioxidant. Antioxidants block some of the damage caused by free radicals, substances that damage DNA, the body’s genetic material. Over time, the accumulation of free radicals may contribute to the aging process and the development of a number of health conditions such as cancer, heart disease, arthritis, and cataracts.

Vitamin C also assists in the formation of collagen, a protein which is important for the health of blood vessels and gums, development of bones and teeth, and wound healing. In addition, Vitamin C improves the absorption of iron from plant-based foods and helps the immune system work properly to protect the body from disease.

Vitamin C deficiency is rare in North America. People who get little or no Vitamin C for many weeks can develop scurvy. Scurvy causes fatigue, depression, swollen and/or bleeding gums, loosening or loss of teeth, small red or purple spots on the skin, joint pain, poor wound healing, corkscrew hairs, and anemia. Scurvy is fatal if it is not treated.

Taking too much Vitamin C is also rare. When it occurs, it can lead to diarrhea, nausea, and stomach cramps. In people with a condition called hemochromatosis, which causes the body to store too much iron, high doses of Vitamin C could worsen iron overload and lead to the damage of body tissues.

Top Vitamin C–Rich Foods

Vegetables and fruit are the best sources of Vitamin C.

Food	Vitamin C per serving
Guava, 1/2 cup	188.3 mg
Bell pepper, red, raw, chopped, 1/2 cup	95.1 mg
Kiwi fruit, sliced, 1/2 cup	83.4 mg
Papaya, mashed, 1/2 cup	70 mg
Lychee, 1/2 cup	67.9 mg
Brussels sprouts, cooked, 4 sprouts	64.6 mg
Orange juice, 1/2 cup	62.0 mg
Bell pepper, green, raw, chopped, 1/2 cup	59.9 mg
Navel orange, 1/2 cup	48.8 mg
Strawberries, sliced, 1/2 cup	48.8 mg
Grapefruit, 1/2 fruit	45.5 mg
Broccoli, raw, chopped, 1/2 cup	40.6 mg
Pineapple, chunks, 1/2 cup	39.4 mg
Cabbage, red, raw, 1/2 cup	25.4 mg

Nutrition Facts Label and the % Daily Value

In the United States: The daily value (DV) for Vitamin C is 60 mg, which is lower than the DRI for adults. The number you see on the Nutrition Facts label is a percentage calculated by dividing the amount of Vitamin C in one serving of the food by the DV. Using an example from the above chart, ½ cup of mashed papaya, which contains 70 mg of Vitamin C, would have 117% of the DV for Vitamin C. The FDA requires that the DV for Vitamin C be listed on the Nutrition Facts label.

In Canada: The daily value for Vitamin C in Canada is also 60 mg. Canadian labeling laws also require that the DV for Vitamin C be listed on the Nutrition Facts label.

Nutrient Interactions

Iron: Vitamin C (from food sources and/or supplements) increases the absorption of iron when taken at the same time.

Copper: Supplemental intake of Vitamin C at very large doses (1,500 mg daily) can interfere with copper metabolism.

Vitamin E: Vitamin C is involved in the regeneration of Vitamin E, and these two vitamins appear to work together in their antioxidant effect.