Biotin Status in Infants Fed Breast Milk and Formula

Abstract

We have pointed out that biotin is scarcely included in special formulas made in Japan. In this study, we describe the biotin status in 22 infants with phenylketonurea (PKU) who have been fed special formulas. Serum free and total biotin level, biotinidase activity, vitamin B₁₂, folate level, urine biotin, 3-hydroxyisovaleric acid (3-HIA), lactate, pyruvate and creatinine (Cre) were measured and compared with healthy infants fed breast milk and formula. Serum total biotin level (2.5±0.4 ng/mL) and biotinidase activity (6.6±0.9 nmol/min/mL) in infants with PKU were in the normal range and there were not significant differences compared with those in the 18 infants fed breast milk (2.3±0.6 ng/mL and 5.0±1.3 nmol/min/mL, respectively). In the urine of infants with PKU, the biotin level (16.8± 24.2 μg/g Cre) was significantly lower than infants fed breast milk (70.2±61.8 μg/g Cre). 3-HIA, lactate and pyruvate levels tended to be high. It is shown that the state of low biotin levels is latent in infants fed special milk.