Article

Polyphenols excreted in urine as biomarkers of total polyphenol intake

Nutrition & Food Science Department, XaRTA, Instituto de Investigaciónen Nutrición y Seguridad Alimentaria, Pharmacy School, University of Barcelona, Barcelona, Spain.
Bioanalysis (Impact Factor: 3). 11/2012; 4(22):2705-13. DOI: 10.4155/bio.12.249
Source: PubMed

ABSTRACT

Background:
Nutritional biomarkers have several advantages in acquiring data for epidemiological and clinical studies over traditional dietary assessment tools, such as food frequency questionnaires. While food frequency questionnaires constitute a subjective methodology, biomarkers can provide a less biased and more accurate measure of specific nutritional intake. A precise estimation of polyphenol consumption requires blood or urine sample biomarkers, although their association is usually highly complex.

Results:
This article reviews recent research on urinary polyphenols as potential biomarkers of polyphenol intake, focusing on clinical and epidemiological studies. We also report a potentially useful methodology to assess total polyphenols in urine samples, which allows a rapid, simultaneous determination of total phenols in a large number of samples.

Conclusion:
This methodology can be applied in studies evaluating the utility of urinary polyphenols as markers of polyphenol intake, bioavailability and accumulation in the body.

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Available from: Alexander Medina-Remón
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    • "Thus, it can be concluded from the urine excretion results that, among the three groups, the bioavailability of HT was more effective after the diet supplementation with OLE. In fact, it has been established that 24 h-urine offers advantages over plasma measurements, mostly because they allow an accurate evaluation of the total polyphenols absorbed due to the very short plasma half-lives of the polyphenols (Medina-Remón, Tresserra-Rimbau, Arranz, Estruch, & Lamuela-Raventos, 2012 ). Regarding the colonic phenolic metabolites detected in the intestinal contents and faeces, a very low concentration of these metabolites was detected in the urine samples, and no significant differences were observed among the three groups or compared to the control (data not shown). "
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