          
               Vitamin C (ascorbic acid) is a water-soluble vitamin 
          found in a variety of fruits and vegetables that is easily 
          destroyed when exposed to air, heat and light.
          
               Functions: Essential for growth and maintenance of all 
          cells and tissues; promotes the absorption of iron in the 
          intestines; and acts as a water-soluble antioxidant in the 
          body.
          
               Sources: Many fruits and vegetables, including citrus 
          fruits, cantaloupe, strawberries, tomatoes, green and red 
          peppers, kale, collards, mustard greens, broccoli, cabbage, 
          and potatoes.
          
               Deficiency: Signs of deficiency include delayed wound 
          healing; increased susceptibility to infection; and scurvy, 
          a condition characterized by bleeding under the skin, 
          anemia, joint tenderness and swelling, poor wound healing, 
          weakness, and such oral disorders as bleeding gums, tooth 
          loss, and gingivitis. However, because vitamin C sources 
          are plentiful in the U.S. food supply, deficiency is rarely 
          seen; it mainly occurs n infants fed cow's milk only, or in 
          people whose diets lack adequate sources of vitamin C. In 
          addition, cigarette smokers have lower blood levels of 
          vitamin C than nonsmokers. As a consequence, the National 
          Research Council recommends that smokers consume at least 
          100 milligrams of vitamin C per day.
          
               Excess: High intakes of 1 gram or more per day may 
          cause nausea, abdominal cramps, and diarrhea in some 
          people.
          
          
