title: A Taiwanese food frequency questionnaire correlates with plasma docosahexaenoic acid but not with plasma eicosapentaenoic acid levels: questionnaires and plasma biomarkers.
abstract: BACKGROUND
  Little evidence is available for the validity of dietary fish and polyunsaturated fatty acid intake derived from interviewer-administered questionnaires and plasma docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) concentration.
  
  
  METHODS
  We estimated the correlation of DHA and EPA intake from both questionnaires and biochemical measurements. Ethnic Chinese adults with a mean (± SD) age of 59.8 (±12.8) years (n = 297) (47% women) who completed a 38-item semi-quantitative food-frequency questionnaire and provided a plasma sample were enrolled. Plasma fatty acids were analyzed by capillary gas chromatography.
  
  
  RESULTS
  The Spearmen rank correlation coefficients between the intake of various types of fish and marine n-3 fatty acids as well as plasma DHA were significant, ranging from 0.20 to 0.33 (P < 0.001). In addition, dietary EPA, C22:5 n-3 and DHA were significantly correlated with the levels of marine n-3 fatty acids and DHA, with the Spearman rank correlation coefficients ranging from 0.26 to 0.35 (P < 0.001). Moreover, compared with those in the lowest fish intake quintile, participants in the highest quintile had a significantly higher DHA level (adjusted mean difference, 0.99 ± 0.10%, test for trend, P < 0.001). Similar patterns between dietary DHA intake and plasma DHA levels were found. However, the association between dietary fish intake and plasma EPA was not significant (test for trend, P = 0.69).
  
  
  CONCLUSIONS
  The dietary intakes of fish and of long chain n-3 fatty acids, as determined by the food frequency questionnaire, were correlated with the percentages of these fatty acids in plasma, and in particular with plasma DHA. Plasma DHA levels were correlated to dietary intake of long-chain n-3 fatty acids.
authors: Institute of Epidemiology and Preventive Medicine, College of Public School, National Taiwan University, Taipei, Taiwan. klchien@ntu.edu.tw
authors: Kuo-Liong
authors: KL
authors: Chien
authors: Meei-Shyuan
authors: MS
authors: Lee
authors: Yi-Tsen
authors: YT
authors: Tsai
authors: Pey-Rong
authors: PR
authors: Chen
authors: Hung-Ju
authors: HJ
authors: Lin
authors: Hsiu-Ching
authors: HC
authors: Hsu
authors: Yuan-The
authors: YT
authors: Lee
authors: Ming-Fong
authors: MF
authors: Chen
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D004032:Diet; D004281:Docosahexaenoic Acids / Q000097:blood*; D015118:Eicosapentaenoic Acid / Q000097:blood*; D005227:Fatty Acids / Q000097:blood; D005247:Feeding Behavior; D005260:Female; D005399:Fishes; D006801:Humans; D008297:Male; D008875:Middle Aged; D011795:Surveys and Questionnaires; D013624:Taiwan
chemical_list: D015415:Biomarkers; D005227:Fatty Acids; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid