Investigation of the reliability of 24 h urine exreation as a biomarker of isoflavone exposure over time and over a wide range of isoflavone intakes

Objective: To study the variation in genistein+daidzein intake over a 6-month period and test the reliability of 24 h urinary isoflavones as a biomarker of exposure over time. Design: Dietary genistein+daidzein intake was assessed at various time points throughout six months in 15 healthy subjects....

Full description

Saved in:
Bibliographic Details
Published in:European journal of clinical nutrition 2004-09, Vol.58 (9), p.1286
Main Authors: Rtichie, M R, Morton, M S, A M Thompson, N Deighton
Format: Article
Language:English
Subjects:
Clinical nutrition
Diet
Excretion
Exposure
Reliability
Standard deviation
Urine
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Objective: To study the variation in genistein+daidzein intake over a 6-month period and test the reliability of 24 h urinary isoflavones as a biomarker of exposure over time. Design: Dietary genistein+daidzein intake was assessed at various time points throughout six months in 15 healthy subjects. Group 1 (n=8) followed nonsupplemented diets and Group 2 (n=7) took a 35 mg/d isoflavone supplement for 3 months and each subject provided a 24 h urine collection, validated with para-aminobenzoic acid, during weeks 7, 15 and 19. Urine was analysed for genistein and daidzein using LC-MS. Results: Isoflavone intake in Groups 1 and 2 ranged from 0.00 to 1.1 mg/d and 0.1 to 53.1 mg/d, respectively. Urine excretion for both groups ranged from 0.20 to 9.56 mg/d. The relationship between 24 h excretion and isoflavone intake is y=0.44 +/- 0.03(standard deviation) + 1.57; r=0.89, P
ISSN:0954-3007
1476-5640
DOI:10.1038/sj.ejcn.1601963