Vitamin C

Vitamin C is needed for the growth and repair of tissues in all parts of your body. It is used to:

• Form an important protein called collagen, used to make skin, tendons, ligaments, and blood vessels
• Heal wounds and form scar tissue
• Repair and maintain cartilage, bones, and teeth
• Aid in the absorption of iron

Vitamin C is one of many antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals.

• Free radicals are made when your body breaks down food or when you are exposed to tobacco smoke or radiation.
• The buildup of free radicals over time is largely responsible for the aging process.
• Free radicals may play a role in cancer, heart disease, and conditions like arthritis.

The body is not able to make vitamin C on its own. It does not store vitamin C. It is therefore important to include plenty of vitamin C-containing foods in your daily diet.

For many years, vitamin C has been a popular household remedy for the common cold.

• Research shows that for most people, vitamin C supplements or vitamin C-rich foods do not reduce the risk of getting the common cold.
• However, people who take vitamin C supplements regularly might have slightly shorter colds or somewhat milder symptoms.
• Taking a vitamin C supplement after a cold starts does not appear to be helpful.

All fruits and vegetables contain some amount of vitamin C.

Fruits with the highest content of vitamin C include:

• Cantaloupe
• Citrus fruits and juices, such as orange and grapefruit
• Kiwi fruit
• Mango
• Papaya
• Pineapple
• Strawberries, raspberries, blueberries, and cranberries
• Watermelon

Vegetables with the highest sources of vitamin C include:

• Broccoli, Brussels sprouts, and cauliflower
• Green and red peppers
• Spinach, cabbage, turnip greens, and other leafy greens
• Sweet and white potatoes
• Tomatoes and tomato juice
• Winter squash

Some cereals and other foods and beverages are fortified with vitamin C. Fortified means a vitamin or mineral has been added to the food. Check the product labels to see how much vitamin C is in the product.

The best food sources of vitamin C are uncooked or raw fruits and vegetables. Cooking vitamin C-rich foods or storing them for a long period of time can reduce the vitamin C content. Microwaving and steaming vitamin C-rich foods may reduce cooking losses. Exposure to light can also reduce vitamin C content. Choose orange juice that is sold in a carton instead of a clear bottle.

Serious side effects from too much vitamin C are very rare, because the body cannot store the vitamin. However, amounts greater than 2,000 mg/day are not recommended. Doses this high can lead to stomach upset and diarrhea, and rarely, kidney stones. Large doses of vitamin C supplementation are not recommended during pregnancy. They can lead to shortage of vitamin C in the baby after delivery.

Too little vitamin C can lead to signs and symptoms of deficiency, including:

• Anemia
• Bleeding gums
• Decreased ability to fight infection
• Decreased wound-healing rate
• Dry and splitting hair
• Easy bruising
• Gingivitis (inflammation of the gums)
• Nosebleeds
• Possible weight gain because of slowed metabolism
• Rough, dry, scaly skin
• Swollen and painful joints
• Weakened tooth enamel

A severe form of vitamin C deficiency is known as scurvy. This mainly affects older, malnourished adults.

Dietary reference intakes for vitamin C:

Infants (AI)

• 0 to 6 months: 40 milligrams/day (mg/day)
• 7 to 12 months: 50 mg/day

Children (RDA)

• 1 to 3 years: 15 mg/day
• 4 to 8 years: 25 mg/day
• 9 to 13 years: 45 mg/day

Adolescents

• Girls 14 to 18 years: 65 mg/day
• Pregnant teens: 80 mg/day
• Breastfeeding teens: 115 mg/day
• Boys 14 to 18 years: 75 mg/day

Adults

• Men age 19 and older: 90 mg/day
• Women age 19 year and older: 75 mg/day
• Pregnant women: 85 mg/day
• Breastfeeding women: 120 mg/day

Ascorbic acid; Dehydroascorbic acid