title: Alkylresorcinols as biomarkers of whole-grain wheat and rye intake: plasma concentration and intake estimated from dietary records.
abstract: BACKGROUND
  Alkylresorcinols (ARs), phenolic lipids exclusively present in the outer parts of wheat and rye grains, have been proposed as specific dietary biomarkers of whole-grain wheat and rye intake.
  
  
  OBJECTIVE
  The objective was to validate plasma ARs as a biomarker of whole-grain wheat and rye intakes by studying the correlation between their plasma concentration and intake calculated from food records.
  
  
  METHODS
  In a randomized crossover study, 22 women and 8 men were given a defined amount of either whole-grain or refined-cereal-grain products to be included in their habitual diets for two 6-wk periods. Blood samples were collected and food intakes were recorded before and after each intervention period.
  
  
  RESULTS
  Plasma AR concentrations were significantly higher after the whole-grain diet period than after the refined-grain period (P < 0.0001) and were well correlated with average daily AR intake estimated by self-reported weighed food records (Spearman's r = 0.58, P < 0.001).
  
  
  CONCLUSIONS
  Plasma AR concentrations are correlated with intake assessed by food records, which suggests that ARs are selective nutritional biomarkers for the intake of whole-grain wheat and rye.
authors.affiliation: Department of Food Science, Swedish University of Agriculture Science, Uppsala, Sweden. rikard.landberg@lmv.slu.se
authors.forename: Rikard
authors.initials: R
authors.lastname: Landberg
authors.forename: Afaf
authors.initials: A
authors.lastname: Kamal-Eldin
authors.forename: Agneta
authors.initials: A
authors.lastname: Andersson
authors.forename: Bengt
authors.initials: B
authors.lastname: Vessby
authors.forename: Per
authors.initials: P
authors.lastname: Aman
mesh_terms: D015415:Biomarkers / Q000097:blood; D018592:Cross-Over Studies; D004032:Diet; D015930:Diet Records; D004043:Dietary Fiber / Q000008:administration & dosage; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D012118:Resorcinols / Q000008:administration & dosage* / Q000097:blood*; D012434:Secale / Q000737:chemistry; D018709:Statistics, Nonparametric; D014908:Triticum / Q000737:chemistry
chemical_list: D015415:Biomarkers; D004043:Dietary Fiber; D012118:Resorcinols