title: Table of Phenylalanine Content of Foods: Comparative Analysis of Data Compiled in Food Composition Tables.
abstract: BACKGROUND
  Knowing the phenylalanine (Phe) content of foods is essential for managing the diet of patients with phenylketonuria. Data on the Phe content of foods are scarce and sometimes vary between different Food Composition Tables (FCT). Brazil created its own table of the Phe contents of fruits and vegetables based exclusively on the chemical analysis of protein content, considering that proteins contain 3-4% Phe (TCFA/ANVISA). This study compared the protein and Phe contents of vegetables and fruits provided by the TCFA/ANVISA with those listed in international food composition tables.
  
  
  METHODS
  The Phe content of 71 fruits and vegetables listed in TCFA/ANVISA was classified into four subgroups, and the Wilcoxon nonparametric test compared the Phe and mean protein contents provided by the FCTs. All tests considered the bilateral hypothesis, and the level of significance was set at 5%. The Spearman's correlation coefficient measured the statistical dependence between Phe and protein contents.
  
  
  RESULTS
  The mean Phe content was <50 mg Phe/100 g for 15 fruits; >50 mg/100 g for 11 type-A vegetables; <50 mg/100 g for 8 type-B vegetables; ≤50 mg/100 g for 7 type-C vegetables. The percentage of Phe in protein varied from 3.13 ± 1.03% to 3.74 ± 2.55% in fruits; 3.33 ± 1.41 to 4.82 ± 1.17 in type-A vegetables; 3.46 ± 1.25% to 4.83 ± 2.46 in type-B vegetables; and 3.14% ± 1.49 to 4.62% ± 2.26 in type-C vegetables.
  
  
  CONCLUSIONS
  The Phe and protein contents provided by most FCTs were positively correlated, suggesting that it is possible to estimate the Phe content of fruits by multiplying its protein content by 3%. For type-A, -B, and -C vegetables, 4% may be used.
authors.affiliation: National Health Surveillance Agency (ANVISA), SIA Trecho 5, Área Especial 57, Bloco D, 2° andar, Brasília, DF, 71205-050, Brazil. anamarquim@gmail.com.
authors.forename: Ana Claudia Marquim F
authors.initials: ACMF
authors.lastname: Araújo
authors.affiliation: Departamento de Nutrição, Universidade de Brasília, Campus Universitário Darcy Ribeiro - Asa Norte, 70904-110, Brasília, DF, Brazil.
authors.forename: Wilma M C
authors.initials: WMC
authors.lastname: Araújo
authors.affiliation: Faculdade de Ciências Farmacêuticas, Departamento de Alimentos e Nutrição Experimental, Universidade de São Paulo, Av.Prof.Lineu Prestes, 580 - Cidade Universitária, 05508-900, São Paulo, SP, Brazil.
authors.forename: Ursula M Lanfer
authors.initials: UML
authors.lastname: Marquez
authors.affiliation: Departamento de Nutrição, Universidade de Brasília, Campus Universitário Darcy Ribeiro - Asa Norte, 70904-110, Brasília, DF, Brazil.
authors.forename: Rita
authors.initials: R
authors.lastname: Akutsu
authors.affiliation: Universidade de Brasília. Departamento de Estatística, Campus Universitário Darcy Ribeiro - Asa Norte, 70904-110, Brasília, DF, Brazil.
authors.forename: Eduardo Y
authors.initials: EY
authors.lastname: Nakano
keywords: Food composition tables; Phenylalanine; Phenylalanine restricted diet; Phenylketonuria