Development of a food frequency questionnaire for the assessment of quercetin and naringenin intake

• Published in: European journal of clinical nutrition Vol. 62; no. 9; pp. 1131 - 1138
• Main Authors: Ranka, S, Gee, J.M, Biro, L, Brett, G, Saha, S, Kroon, P, Skinner, J, Hart, A.R, Cassidy, A, Rhodes, M
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.09.2008; Nature Publishing; Nature Publishing Group
• Subjects: accuracy; administration & dosage; Adult; adults; Aged; Aged, 80 and over; Aglycones; analysis; Bioflavonoids; Biological and medical sciences; Clinical Nutrition; Diet; Diet Records; Dietary intake; dose response; Epidemiologic Methods; Epidemiology; estimation; Excretion; Feeding. Feeding behavior; Female; Flavanones; Flavanones - administration & dosage; Flavanones - analysis; Flavanones - urine; Flavones; Flavonoids; Food; food frequency questionnaires; Food intake; Fundamental and applied biological sciences. Psychology; High-performance liquid chromatography; Human nutrition; Humans; Hydrolysis; Internal Medicine; Liquid chromatography; Male; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Metabolites; Methods; Middle Aged; Naringenin; Nutrition; Nutrition surveys; Nutritive Value; original-article; Phytochemicals; Public Health; Quercetin; Quercetin - administration & dosage; Quercetin - analysis; Quercetin - urine; Questionnaires; Solid phases; Statistical analysis; Statistical methods; Surveys and Questionnaires; Urine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; United Kingdom; naringenin; FFQ; quercetin; cancer; flavonoids; portion size; Consumption; Human; Urine; Excretion; Naringenin; Metabolic diseases; Malignant tumor; Antioxidant; Flavonoid; Flavanone derivatives; Polyphenol; Quercetin; Phenols; Flavone(3-hydroxy); Food Frequency Questionnaire; Portion; Cancer
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1602827

Objectives: To measure the relationship between quercetin and naringenin intakes as estimated by food frequency questionnaire (FFQ), and the urinary excretion of quercetin and naringenin aglycones after their enzymatic hydrolysis in human volunteers. Subjects and methods: Volunteers were recruited via the Human Nutrition Unit volunteer databank at the Institute of Food Research, Norwich. Sixty-three volunteers were recruited into the study, of which 14 were excluded and 49 completed the study. A modified FFQ was developed and used to estimate daily intake of quercetin and naringenin in 49 healthy volunteers who also provided five 24-h urine samples over a 2-week period. Urinary excretion of quercetin and naringenin metabolites was determined by solid-phase extraction and high-pressure liquid chromatography. Results: The estimated mean intakes of quercetin and naringenin were 29.4 mg (s.d. 15.0) and 58.1 mg (s.d. 62.7) per day, respectively. Mean urinary excretion of quercetin was 60.1 micrograms (s.d. 33.1) and that of naringenin was 0.56 mg (s.d. 0.4). The correlation between FFQ estimated intake of quercetin and naringenin and levels excreted in the urine were r=0.82 (P<0.0001) and r=0.25 (P=0.05), respectively. Conclusions: We observed a statistically significant correlation between the urinary excretion of quercetin and naringenin metabolites and their dietary intake as estimated by FFQ. Use of FFQs in epidemiological studies requiring an estimate of flavonoid intake seems justified.