Who needs extra vitamin C?

The answer is b. Smokers require higher quantities of Vitamin C than the normal daily requirement.

Research has shown that cigarette smoke has a negative impact on the metabolism of vitamin C. Smokers have been found to have a much lower level of ascorbic acid (the other name for vitamin C) in the blood than do nonsmokers. The Food and Nutrition Board recommends that smokers consume 100 mg of vitamin C a day. Besides smokers, chronic alcohol consumers, diabetics and even young women have been found to need higher levels of vitamin C than the recommended 60 milligrams.

Medical experts call vitamin C the 'wonder worker' because it is involved in a number of key life sustaining functions of preventing many illnesses, from everyday ailments such as the common cold to devastating diseases such as cancer. Primarily, vitamin C is involved in collagen formation, which is the cementing material that binds cells together, and is an essential connective tissue protein in the body. Whenever the body is wounded, collagen glues the separated tissues together to form a scar.

Vitamin C also strengthens and protects the immune system by fighting off foreign invaders and by stimulating the activity of antibodies. Recent research has indicated that vitamin C is an important anti-oxidant and may be associated with delayed aging and prevention of diseases like cancer by destroying 'free radicals,' the molecules associated with aging and cell damage.

Although we depend on this nutrient for many aspects of our biochemical functioning, human beings are among only a handful of animal species that cannot produce their own supply of vitamin C. We therefore must obtain it from our diet. Since vitamin C is a water-soluble vitamin, the body eliminates it, which means people need a continuous supply of it in their food.

Resources:

Learn more about recommended doses from the publication, Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids, published by Food and Nutrition Board, part of the Institute of Medicine. Chapter 5 covers recommendations for vitamin C.

The Ohio State University Extension Service provides a basic fact sheet on vitamin C.