Assessment of Dietary Intakes, Blood Parameters and Nutritional Statuses of Children and Adolescents with Phenylketonuria

Due to the limited intakes of routine protein sources in phenylketonuria, nutritional deficiencies may occur. Therefore, the aim of the present study was to assess dietary intakes, blood parameters and nutritional statuses of children and adolescents with phenylketonuria.

In total, 80 patients with phenylketonuria (42 girls, 52.5%) were included in this cross-sectional study. Using general information questionnaires, necessary information linked to nutritional and demographic indicators were collected. Patients' diets were assessed using a 3-day diet recall. Blood concentrations of phenylalanine, tyrosine, ferritin, iron, zinc, folic acid, B12, 25-hydroxyvitamin D3, albumin and calcium were assessed.

The present study showed that the highest frequency was allocated to people with normal weight with a frequency of 57.5% based on body mass index for age. In this study, children and adolescents with phenylketonuria, who were low and normal weight, had higher serum iron levels (p = 0.006) and their calcium intake was higher (p = 0.007). Additionally, participants consumed fewer calories, zinc and vitamin B12 and more fat, phenylalanine, tyrosine, iron and calcium, compared to the recommended values. The current study results showed that phenylalanine levels were higher than the acceptable levels in the majority of participants.

Results of this study demonstrated importance of iron supplementation for obese children and adolescents with phenylketonuria. Since the serum level of phenylalanine in these people was greater than the acceptable level, it is recommended to use necessary measures to follow and provide special diets for these patients.