We all dread the misery that a common cold brings and many people hope that taking vitamin C supplements will help prevent a cold. Numerous research studies on vitamin C have provided the following information about the action of vitamin C in the body.

What does vitamin C do in the body? It is needed for the formation of connective tissues, blood vessels, teeth and bones. Vitamin C also is important for normal immune function and for healing wounds. Its antioxidant activity helps prevent damage to cells.

What foods are the best sources of vitamin C? Most fruits and vegetables contain some vitamin C. The best sources include red and green peppers, citrus fruits, guava, mango, papaya, broccoli, Brussels sprouts, strawberries, kiwi fruit, cantaloupe, collard greens, cabbage and potatoes.

How should fruits and vegetables be prepared to keep vitamin C levels high? Exposure to air destroys vitamin C so eat fruits and vegetables raw and unpeeled, if possible. Do not cut into small pieces or leave exposed to air for a long time. Vitamin C leaches into water so stir fry or microwave or steam vegetables using only a small amount of water.

How much vitamin C does a person need? The RDA for adult males is 90 mg and for adult females is 75 mg. When more than 200 mg is consumed daily, it is excreted in the urine.

Is it dangerous to take high dose vitamin C supplements? Doses above 1,000 mg daily increase the risk of kidney stones and may cause nausea and diarrhea.

Does vitamin C help fight colds? A recent comprehensive review of 60 years of research worldwide on vitamin C supplements and colds came to the following conclusions:

• Taking a vitamin C supplement does not prevent a person from getting a cold

• If vitamin C is taken as a daily preventive supplement (before coming down with a cold), it very slightly shortens the duration of the cold

• Taking vitamin C after a cold starts does not make the cold shorter or less severe

The best way to stay healthy in the cold season is to wash your hands frequently, eat a balanced diet and exercise regularly. (And keep your distance from people with colds!)

Small step reminder for a healthier new year: Fill half your plate with vegetables at dinner.

Christine Gutelius, MA, RD, CDN, is a nutrition resource educator with the Eat Smart NY program at Cornell Cooperative Extension of Cayuga County.

Stir Fried Broccoli

Makes 4 cups

1 teaspoon oil

2 cloves garlic, minced, or 2 teaspoons bottled minced garlic

1/8 teaspoon ginger

1 pound frozen broccoli florets, thawed and drained

2 tablespoons water

2 teaspoons soy sauce

Heat oil in skillet or wok.

Add garlic and broccoli. Stir-fry to coat with oil.

Add water, ginger and soy sauce.

Continue to stir-fry until broccoli is bright green and crisp-tender, about 3 to 4 minutes.

Serve immediately.