Niacin

           

          

          Niacin

          

          

                            U.S. Recommended Daily Allowances

          

          Infants      Children      Adults and           Pregnant or

          

          (0-12 mo.)   (1-3 years)   Children 4 Years +   Nursiing Women

          

          8 mg         9 mg          20 mg                20 mg

          

              (The U.S. RDA amounts are sufficient to meet the needs 

          of practically all healthy people.)

          

               Niacin (nicotinic acid, nicotinamide) is a 

          water-soluble vitamin whose requirement is partly met by 

          conversion in the body of the essential amino acid 

          tryptophan to niacin.

          

               Functions: Involved in carbohydrate, protein and fat 

          metabolism.

          

               Sources: Enriched cereal-grain products; meat, fish, 

          poultry, cheese, eggs, and milk because they contain 

          tryptophan; peanuts; mushrooms; potatoes.

          

               Deficiency: Severe niacin deficiency causes pellagra, 

          a disease characterized by mouth sores, skin rashes, 

          diarrhea, and dementia.  Deficiency is rarely seen in the 

          United States, though, because most people have adequate 

          intakes.

          

               Excess: Large amounts of niacin, when taken in the 

          nicotinic acid form of the vitamin, act as a drug. 

          Nicotinic acid is often prescribed as a 

          cholesterol-lowering drug, and should be taken only under 

          the supervision of a physician. Side effects include 

          vascular dilation of the skin (flushing) and 

          gastrointestinal distress. Prolonged intake may cause liver 

          damage.

          

               Nicotinamide is not known to act as a drug. Effects of 

          high doses are unknown.