Biotin
          

               U.S. Recommended Daily Allowances
          
             Infants      Children    Adults and           Pregnant or
          
            (0-12 mo.)    (1-3 years) Children 4 Years +  Nursing Women
          
            50 micrograms 150 mcg     300 mcg               300 mcg
          
               (The U.S. RDA amounts are sufficient to meet the needs 
          of practically all healthy people. FDA set these based on 
          the 1968 Recommended Dietary Allowances by the National 
          Research Council of the National Academy of Sciences. 
          However, in 1989, the council lowered its ranges of safe 
          and adequate daily dietary intakes for biotin to 10 to 15 
          micrograms for infants, 20 to 30 mcg for children, and 30 
          to 100 mcg for adults. FDA is in the process of revising 
          its U.S. RDAs.)
          
               Biotin is a sulfur-containing, B-complex vitamin found 
          in foods and produced by microorganisms in the lower 
          gastrointestinal tract.
          
               Functions: Activates certain enzymes that aid in 
          metabolism of carbon dioxide; involved in metabolism of 
          protein, fats and carbohydrates.
          
               Sources: Widely distributed in foods that are sources 
          of B vitamins, including cereal-grain products, liver, egg 
          yolk, soy flour, and yeast.
          
               Deficiency: Signs include loss of appetite, nausea, 
          vomitting, inflammation of the tongue, pallor, depression, 
          hair loss, and dry, scaly skin. Some rare biotin-related 
          inborn errors of metabolism may cause deficiency; 
          otherwise, deficiency is extremely rare in the United 
          States.
          
               Excess: No effects have been reported.