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

Abstract EN

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.