Metabolomic Insights into the Nutritional Status of Adults and Adolescents with Phenylketonuria Consuming a Low-Phenylalanine Diet in Combination with Amino Acid and Glycomacropeptide Medical Foods

Background. nutrient status in phenylketonuria (pku) requires surveillance due to the restrictive low-phe diet in combination with amino acid medical foods (aa-mf) or glycomacropeptide medical foods (gmp-mf). micronutrient profiles of medical foods are diverse,and optimal micronutrient supplementation in pku has not been established. methods. in a crossover design,30 participants with pku were randomized to consume aa-mf and glytactin™ gmp-mf in combination with a low-phe diet for 3 weeks each. fasting venipunctures,medical food logs,and 3-day food records were obtained. metabolomic analyses were completed in plasma and urine by metabolon,inc. results. the low-phe diets in combination with aa-mf and gmp-mf were generally adequate based on dietary reference intakes,clinical measures,and metabolomics. without micronutrient supplementation of medical foods,>70% of participants would have inadequate intakes for 11 micronutrients. despite micronutrient supplementation of medical foods,inadequate intakes of potassium in 93% of participants and choline in >40% and excessive intakes of sodium in >63% of participants and folic acid in >27% were observed. sugar intake was excessive and provided 27% of energy. conclusions. nutrient status was similar with aa-mf and glytactin gmp-mf. more research related to micronutrient supplementation of medical foods for the management of pku is needed. © 2017 bridget m. stroup et al.