Vitamin C
Last Updated on Sunday, 28 February 2010 21:08
Vitamin C, also known as L-ascorbic acid, is a water-soluble vitamin that is naturally required for the biosynthesis of collagen, L-carnitine, and certain neurotransmitters. Collagen is an essential component of connective tissue, which plays a vital role in wound healing. Vitamin C is also involved in protein metabolism. is an important physiological antioxidant and has been shown to regenerate other antioxidants within the body, including alpha-tocopherol (vitamin E).
Ongoing research is examining whether vitamin C, by limiting the damaging effects of free radicals through its antioxidant activity, might help prevent or delay the development of certain cancers, cardiovascular disease, and other diseases in which oxidative stress plays a causal role. In addition to its biosynthetic and antioxidant functions, vitamin C plays an important role in immune function and improves the absorption of nonheme iron, the form of iron present in plant-based foods.
Insufficient vitamin C intake causes scurvy, which is characterized by fatigue or lassitude, widespread connective tissue weakness, and capillary fragility.
Recommended Intake
The Food & Nutrition Board at the Institute of Medicine of the National Academies established adequate daily dietary intake allowances for vitamin C. They are listed below in milligrams (mg) per day.
| Age | Male | Female | Pregnancy | Lactation |
|---|---|---|---|---|
| Birth to 6 months | 40 mg | 40 mg | ||
| 7–12 months | 50 mg | 50 mg | ||
| 1–3 years | 15 mg | 15 mg | ||
| 4–8 years | 25 mg | 25 mg | ||
| 9–13 years | 45 mg | 45 mg | ||
| 14–18 years | 75 mg | 65 mg | 80 mg | 115 mg |
| 19+ years | 90 mg | 75 mg | 85 mg | 120 mg |
| Smokers | Individuals who smoke require 35 mg/day more vitamin C than nonsmokers. | |||
Sources of Vitamin C
| Food | Milligrams (mg) per serving | Percent Daily Value* |
|---|---|---|
| Red pepper, raw, ½ cup | 95 | 158 |
| Orange juice, ¾ cup | 93 | 155 |
| Kiwifruit, 1 medium | 71 | 118 |
| Orange, 1 medium | 70 | 117 |
| Grapefruit juice, ¾ cup | 70 | 117 |
| Green pepper, raw, ½ cup | 60 | 100 |
| Broccoli, cooked, ½ cup | 51 | 85 |
| Strawberries, fresh, ½ cup | 49 | 82 |
| Brussels sprouts, cooked, ½ cup | 48 | 80 |
| Grapefruit, ½ medium | 39 | 65 |
| Broccoli, raw, ½ cup | 39 | 65 |
| Tomato juice, ¾ cup | 33 | 55 |
| Cantaloupe, ½ cup | 29 | 48 |
| Cabbage, cooked, ½ cup | 28 | 47 |
| Cauliflower, raw, ½ cup | 23 | 38 |
| Potato, baked, 1 medium | 20 | 33 |
| Tomato, raw, 1 medium | 16 | 27 |
| Breakfast cereal fortified with 25% of the DV for vitamin C, 1 serving | 15 | 25 |
| Spinach, cooked, ½ cup | 9 | 15 |
| Green peas, cooked, ½ cup | 8 | 13 |
*Daily Values were developed by the U.S. Food and Drug Administration to help consumers compare the nutrient contents among products within the context of a total daily diet. The Daily Value for vitamin C is 60 milligrams for adults and children aged 4 and older. Foods providing 20 percent of more of the Daily Value are considered to be high sources of a nutrient, but foods providing lower percentages of the Daily Value also contribute to a healthful diet.
