1Subar, AF, Thompson, FE, Kipnis, V, et al. (2001) Comparative validation of the Block, Willett, and National Cancer Institute food frequency questionnaires: the Eating at America's Table Study. Am J Epidemiol 154, 1089–1099.
2Willett, WC (1998) Nutritional Epidemiology, 2nd ed.Oxford: Oxford Medical Publications.
3Jenab, M, Slimani, N, Bictash, M, et al. (2009) Biomarkers in nutritional epidemiology: applications, needs and new horizons. Hum Genet 125, 507–525.
4Byers, T, Trieber, F, Gunter, E, et al. (1993) The accuracy of parental reports of their children's intake of fruits and vegetables: validation of a food frequency questionnaire with serum levels of carotenoids and vitamins C, A, and E. Epidemiology 4, 350–355.
5Resnicow, K, Odom, E, Wang, T, et al. (2000) Validation of three food frequency questionnaires and 24-hour recalls with serum carotenoid levels in a sample of African-American adults. Am J Epidemiol 152, 1072–1080.
6Kristal, AR, Vizenor, NC, Patterson, RE, et al. (2000) Precision and bias of food frequency-based measures of fruit and vegetable intakes. Cancer Epidemiol Biomarkers Prev 9, 939–944.
7Bogers, RP, Van Assema, P, Kester, AD, et al. (2004) Reproducibility, validity, and responsiveness to change of a short questionnaire for measuring fruit and vegetable intake. Am J Epidemiol 159, 900–909.
8Andersen, LF, Veierød, MB, Johansson, L, et al. (2005) Evaluation of three dietary assessment methods and serum biomarkers as measures of fruit and vegetable intake, using the method of triads. Br J Nutr 93, 519–527.
9Mikkelsen, TB, Olsen, SF, Rasmussen, SE, et al. (2007) Relative validity of fruit and vegetable intake estimated by the food frequency questionnaire used in the Danish National Birth Cohort. Scand J Public Health 35, 172–179.
10Toft, U, Kristoffersen, L, Ladelund, S, et al. (2008) Relative validity of a food frequency questionnaire used in the Inter99 study. Eur J Clin Nutr 62, 1038–1046.
11Burrows, TL, Warren, JM, Colyvas, K, et al. (2008) Validation of overweight children's fruit and vegetable intake using plasma carotenoids. Obesity 17, 162–168.
12Slater, B, Enes, CC, López, RV, et al. (2010) Validation of a food frequency questionnaire to assess the consumption of carotenoids, fruits and vegetables among adolescents: the method of triads. Cad Saude Publica 26, 2090–2100.
13Crispim, SP, Geelen, A, Souverein, OW, et al. (2011) Biomarker-based evaluation of two 24-h recalls for comparing usual fish, fruit and vegetable intakes across European centers in the EFCOVAL Study. Eur J Clin Nutr 65, S38–S47.
14Nielsen, SE, Freese, R, Kleemola, P, et al. (2002) Flavonoids in human urine as biomarkers for intake of fruits and vegetables. Cancer Epidemiol Biomarkers Prev 11, 459–466.
15Krogholm, KS, Bredsdorff, L, Alinia, S, et al. (2010) Free fruit at workplace increases total fruit intake: a validation study using 24 h dietary recall and urinary flavonoid excretion. Eur J Clin Nutr 64, 1222–1228.
16Brantsæter, AL, Haugen, M, Rasmussen, SE, et al. (2007) Urine flavonoids and plasma carotenoids in the validation of fruit, vegetable, and tea intake during pregnancy in the Norwegian Mother and Child Cohort Study (MoBa). Public Health Nutr 10, 838–847.
17Carlsen, MH, Karlsen, A, Lillegaard, ITL, et al. (2011) Relative validity of fruit and vegetable intake estimated from an FFQ, using carotenoid and flavonoid biomarkers and the method of triads. Br J Nutr 105, 1530–1538.
18Krogholm, KS, Haraldsdottir, J, Knuthsen, P, et al. (2004) Urinary total flavonoid excretion but not 4-pyridoxic Acid or potassium can be used as a biomarker for the intake of fruits and vegetables. J Nutr 134, 445–551.
19Mennen, LI, Sapinho, D, Ito, H, et al. (2006) Urinary flavonoids and phenolic acids as biomarkers of intake for polyphenols-rich foods. Br J Nutr 96, 191–198.
20Mennen, LI, Sapinho, D, Ito, H, et al. (2008) Urinary excretion of 13 dietary flavonoids and phenolic acids in free-living healthy subjects – variability and possible use as biomarkers of polyphenol intake. Eur J Clin Nutr 62, 519–525.
21World Health Organization (1999) Definition, Diagnosis and Classification of Diabetes Mellitus and its Complications. Report of a WHO Consulation. . Geneva: WHO.
22Jorgensen, T, Borch-Johnsen, K, Thomsen, TF, et al. (2003) A randomized non-pharmacological intervention study for prevention of ischaemic heart disease: baseline results Inter99. J Cardiovasc Risk 10, 377–386.
23Saxholt, E, Møller, A & Ygil, K (2005) Danish Food Composition Databank version 6.0 [Fødevaredatabanken version 6.0]. Søborg: Department of Nutrition, The Danish Institute for Food and Veterinary Research. http://www.foodcomp.dk.
25Jakobsen, J, Ovesen, L, Fagt, S, et al. (1997) Para-aminobenzoic acid used as a marker for completeness of 24 h urine: assessment of control limits for specific HPLC method. Eur J Clin Nutr 51, 514–519.
26Nielsen, SE, Freese, R, Cornett, C, et al. (2000) Identification and quantification of flavonoids in human urine samples by column-switching liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry. Anal Chem 72, 1503–1509.
27Nielsen, IL, Haren, GR, Magnussen, EL, et al. (2003) Quantification of anthocyanins in commercial black currant juices by simple high-performance liquid chromatography. Investigation of their pH stability and antioxidative potency. J Agri Food Chem 51, 5861–5866.
28Kaaks, RJ (1997) Biochemical markers as additional measurements in studies of the accuracy of dietary questionnaire measurements: conceptual issues. Am J Clin Nutr 65, 1232S–1239S.
29Ocke, MC & Kaaks, RJ (1997) Biochemical markers as additional measurements in dietary validity studies: application of the method of triads with examples from the European Prospective. Am J Clin Nutr 65, 1240S–1245S.
30R Development Core Team (2005) R: A Language and Environment for Statistical Computing. Vienna: R Foundation for Statistical Computing. http://www.r-project.org/.
31Kilkkinen, A, Stumpf, K, Pietinen, P, et al. (2001) Determinants of serum enterolactone concentration. Am J Clin Nutr 73, 1094–1100.
32Horner, NK, Kristal, AR, Prunty, J, et al. (2002) Dietary determinants of plasma enterolactone. Cancer Epidemiol Biomarkers Prev 11, 121–126.
33Johnsen, NF, Hausner, H, Olsen, A, et al. (2004) Intake of whole grains and vegetables determines the plasma enterolactone concentration of Danish women. J Nutr 134, 2691–2697.
34Milder, IEJ, Feskens, EJM, Arts, ICW, et al. (2005) Intake of the plant lignans secoisolariciresinol, matairesinol, lariciresinol and pinoresinol in Dutch men and women. J Nutr 135, 1202–1207.
35Touillaud, MS, Thiébaut, AC, Fournier, A, et al. (2007) Dietary lignan intake and postmenopausal breast cancer risk by estrogen and progesterone receptor status. J Natl Cancer Inst 99, 475–486.
36Manach, C, Williamson, G, Morand, C, et al. (2005) Bioavailability and bioefficacy of polyphenols in humans. I. Review of 97 bioavailability studies. Am J Clin Nutr 81, 230S–242S.
37Pérez-Jiménez, J, Hubert, J, Hooper, L, et al. (2010) Urinary metabolites as biomarkers of polyphenol intake in humans: a systematic review. Am J Clin Nutr 92, 801–809.
38van Kapple, AL, Steghens, J-P, Zeleniuch-Jacquotte, A, et al. (2001) Serum carotenoids as biomarkers of fruit and vegetable consumption. Public Health Nutr 4, 829–835.
39Kabagambe, EK, Baylin, A, Allan, DA, et al. (2001) Application of the method of triads to evaluate the performance of food frequency questionnaires and biomarkers as indicators of long-term dietary intake. Am J Epidemiol 154, 1126–1135.
40Brevik, A, Veierød, MB, Drevon, CA, et al. (2005) Evaluation of the odd fatty acids 15:0 and 17:0 in serum and adipose tissue as markers of intake of milk and dairy fat. Eur J Clin Nutr 59, 1417–1422.
41McNaughton, SA, Marks, GC, Gaffney, P, et al. (2005) Validation of a food-frequency questionnaire assessment of carotenoid and vitamin E intake using weighed food records and plasma biomarkers: the method of triads model. Eur J Clin Nutr 59, 211–218.
42McNaughton, SA, Hughes, MC & Marks, GC (2007) Validation of a FFQ to estimate the intake of PUFA using plasma phospholipid fatty acids and weighed foods records. Br J Nutr 97, 561–568.