title: Does a lower carbohydrate protein substitute impact on blood phenylalanine control, growth and appetite in children with PKU?
abstract: BACKGROUND
  In children with phenylketonuria (PKU), it is possible that high carbohydrate protein substitutes may adversely affect blood phenylalanine control. We evaluated if a low carbohydrate, 'ready-to-drink' protein substitute would impact on short term blood phenylalanine control, weight and appetite in children with PKU aged 3-10 years.
  
  
  METHODS
  This was a 3-part, 5-week randomised, controlled, crossover study in which two different carbohydrate/protein-equivalent ratios in protein substitute [control protein substitute (CPS) median 1:1; trial protein substitute (TPS) 0.5:1] were compared. The effects on feeding behaviour, weight change and phenylalanine concentrations were studied. Fourteen children (12 boys; median age 6.3 y, range 3 to 9.7 y) with PKU on diet were recruited from 2 treatment centres.
  
  
  RESULTS
  Phenylalanine control did not deteriorate with TPS and remained unchanged between pre-study and CPS (p = 0.783). No statistical differences were noted in energy intake between the two study parts. Any changes in weight were similar between the two groups and there was limited change in feeding behaviour.
  
  
  CONCLUSIONS
  This study suggests that the carbohydrate/protein-equivalent ratio of protein substitutes can be reduced to 0.5:1 with no loss of blood phenylalanine control or adverse effect on weight gain in children with PKU.
authors: Birmingham Children's Hospital, Steelhouse Lane, Birmingham, B4 6NH, UK.
authors: Hulya
authors: H
authors: Gokmen-Ozel
authors: Carol
authors: C
authors: Ferguson
authors: Sharon
authors: S
authors: Evans
authors: Anne
authors: A
authors: Daly
authors: Anita
authors: A
authors: MacDonald
mesh_terms: D000293:Adolescent; D000886:Anthropometry; D001066:Appetite / Q000502:physiology*; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D004040:Dietary Carbohydrates / Q000627:therapeutic use*; D004044:Dietary Proteins / Q000627:therapeutic use*; D019587:Dietary Supplements; D005247:Feeding Behavior; D005260:Female; D048788:Growth and Development; D006801:Humans; D008297:Male; D010649:Phenylalanine / Q000097:blood*; D010661:Phenylketonurias / Q000097:blood* / Q000178:diet therapy* / Q000503:physiopathology
chemical_list: D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D010649:Phenylalanine