Forskning
April 27, 2021
The relationship between urinary polyphenol metabolites and dietary polyphenol intakes in young adults
E D Clarke et al, 2021. The relationship between urinary polyphenol metabolites and dietary polyphenol intakes in young adults, British Journal of Nutrition, published online.
ABSTRACT:
Spot urinary polyphenols have potential as a biomarker of polyphenol-rich food intakes. The aim of this study is to explore the relationship between spot urinary polyphenols and polyphenol intakes from polyphenol-rich food sources. Young adults (18-24 years old) were recruited into a sub-study of an online intervention aimed at improving diet quality. Participants intake of polyphenols and polyphenol-rich foods were assessed at baseline and 3 months using repeat 24-hour recalls. A spot urine sample was collected at each session, with samples analysed for polyphenol metabolites using liquid chromatography-mass spectroscopy. To assess the strength of the relationship between urinary polyphenols and dietary polyphenols, Spearman correlations were used. Linear mixed models further evaluated the relationship between polyphenol intakes and urinary excretion. Total urinary polyphenols and hippuric acid demonstrated moderate correlation with total polyphenol intakes (rs=0.29-0.47). Hippuric acid and caffeic acid were moderately correlated with polyphenols from tea/coffee (rs=0.26-0.46). Using linear mixed models, increases in intakes of total polyphenols or polyphenols from tea/coffee or oil resulted in a greater excretion of hippuric acid. Whereas a negative relationship was observed between soy polyphenols and hippuric acid suggesting that participants that with higher intakes of soy polyphenols had a lower excretion of hippuric acid. Findings suggest that total urinary polyphenols may be a promising biomarker of total polyphenol intakes foods and drinks and that hippuric acid may be a biomarker of total polyphenol intakes and polyphenols from tea/coffee. Caffeic acid warrants further investigation as a potential biomarker of polyphenols from tea/coffee.
