Phenylketonuria and B-Group Vitamins

Abstract

Phenylketonuria (PKU) is an inherited autosomal recessive metabolic disorder caused by a deficiency in the production of the hepatic enzyme phenylalanine hydroxylase (PAH). If the patient is untreated, high phenylalanine (Phe) levels accumulate in the brain and leads to mental retardation. Children with phenylketonuria should be treated with a strict low Phe diet in order to prevent neurological disorders. Dietary treatment is substantially effective in the prevention of mental retardation, however low Phe diet may lead to several micronutrient deficiencies such as vitamin B group, vitamin D, calcium, iron, selenium and zinc due to restriction of animal proteins which consist many of these nutrients. In many studies inadequate intakes of vitamin B group, which are known to play an important role in neurological functions have been determined for patients particularly who give up to consume low FA diet and/or FA free amino acid formulations. In this article, the relationship between PKU-low Phe diets and vitamin B group was reviewed.