Experimental studies have reported on the anti-inflammatory properties of
polyphenols. However, results from epidemiological investigations have been inconsistent and especially studies using
biomarkers for assessment of
polyphenol intake have been scant. We aimed to characterise the association between plasma concentrations of thirty-five
polyphenol compounds and low-grade systemic
inflammation state as measured by
high-sensitivity C-reactive protein (
hsCRP). A cross-sectional data analysis was performed based on 315 participants in the European Prospective Investigation into
Cancer and Nutrition cohort with available measurements of plasma
polyphenols and
hsCRP. In logistic regression analysis, the OR and 95 % CI of elevated serum
hsCRP (>3 mg/l) were calculated within quartiles and per standard deviation higher level of plasma
polyphenol concentrations. In a multivariable-adjusted model, the sum of plasma concentrations of all
polyphenols measured (per standard deviation) was associated with 29 (95 % CI 50, 1) % lower odds of elevated
hsCRP. In the class of
flavonoids,
daidzein was inversely associated with elevated
hsCRP (OR 0·66, 95 % CI 0·46, 0·96). Among phenolic
acids, statistically significant associations were observed for
3,5-dihydroxyphenylpropionic acid (OR 0·58, 95 % CI 0·39, 0·86),
3,4-dihydroxyphenylpropionic acid (OR 0·63, 95 % CI 0·46, 0·87),
ferulic acid (OR 0·65, 95 % CI 0·44, 0·96) and
caffeic acid (OR 0·69, 95 % CI 0·51, 0·93). The odds of elevated
hsCRP were significantly reduced for
hydroxytyrosol (OR 0·67, 95 % CI 0·48, 0·93). The present study showed that
polyphenol biomarkers are associated with lower odds of elevated
hsCRP. Whether diet rich in bioactive
polyphenol compounds could be an effective strategy to prevent or modulate deleterious health effects of
inflammation should be addressed by further well-powered longitudinal studies.