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Published on: January 1, 2018
Urinary phytoestrogen concentrations in the U.S. population (1999-2000)
Liza Valentín-Blasini1, Melissa A Sadowski, Donna Walden
1National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA. LValentin@cdc.gov
Summary
Phytoestrogen levels in US adults and adolescents vary by age and race. Enterolactone and daidzein were most common, with differences observed across demographic groups.
Area of Science:
- Environmental Health
- Nutritional Science
- Biomarkers
Background:
- Phytoestrogens are plant-derived compounds with potential health benefits.
- Understanding population exposure is crucial for assessing health impacts.
Purpose of the Study:
- To report population-based urinary concentrations of key phytoestrogens.
- To stratify these concentrations by age, sex, and race/ethnicity.
Main Methods:
- Analysis of approximately 2500 urine samples from the National Health and Nutrition Examination Survey (NHANES) 1999-2000.
- Measurement of isoflavones (genistein, daidzein, equol, O-DMA) and lignans (enterolactone, enterodiol).
- Multivariate statistical analyses to identify demographic differences.
Main Results:
- Phytoestrogens were detected in over 70% of samples; enterolactone and daidzein were most prevalent.
- Geometric means ranged from 3.95 (O-DMA) to 217 (enterolactone) microg/g creatinine.
- Significant demographic variations were observed, with adolescents and non-Hispanic whites showing distinct patterns.
Conclusions:
- Urinary phytoestrogen levels in the US population exhibit significant demographic variability.
- These findings provide a baseline for understanding phytoestrogen exposure.
- Further research can elucidate the role of phytoestrogens in disease prevention.
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