TABLE 3.
Urinary F2-IsoP and 15-F2t-IsoP-M concentrations in healthy women according to tea drinking and urinary excretion of tea polyphenols in the Shanghai Women's Health Study1
| Tertiles from lowest to highest | n | F2-IsoPs | 15-F2t-IsoP-M | ||||||
| Unadjusted2 | P | Adjusted2 | P | Unadjusted2 | P | Adjusted2 | P | ||
| ng/mg creatinine | ng/mg creatinine | ng/mg creatinine | ng/mg creatinine | ||||||
| Tea drinking | 845 | 0.48 | 0.72 | 0.18 | 0.06 | ||||
| Never | 605 | 1.60 (1.54, 1.68)3 | 1.62 (1.54, 1.70) | 0.55 (0.53, 0.58) | 0.56 (0.53, 0.59) | ||||
| Ever | 240 | 1.66 (1.54, 1.79) | 1.65 (1.52, 1.77) | 0.59 (0.55, 0.63) | 0.61 (0.56, 0.66) | ||||
| Polyphenols | 700 | ||||||||
| Epicatechin | 0.82 | 0.55 | 0.38 | 0.42 | |||||
| 0 μmol/g creatinine4 | 325 | 1.60 (1.51, 1.70) | 1.62 (1.52, 1.73) | 0.56 (0.53, 0.59) | 0.58 (0.54, 0.62) | ||||
| >0–0.13 μmol/g creatinine | 142 | 1.54 (1.39, 1.68) | 1.57 (1.42, 1.73) | 0.55 (0.50, 0.61) | 0.56 (0.51, 0.62) | ||||
| >0.13 μmol/g creatinine | 233 | 1.72 (1.58, 1.84) | 1.73 (1.58, 1.87) | 0.59 (0.55, 0.63) | 0.59 (0.53, 0.61) | ||||
| Epigallocatechin | 0.18 | 0.41 | 0.03 | 0.03 | |||||
| <0.03 μmol/g creatinine | 228 | 1.61 (1.48, 1.72) | 1.60 (1.48, 1.78) | 0.55 (0.50, 0.59) | 0.55 (0.52, 0.60) | ||||
| 0.03–0.28 μmol/g creatinine | 238 | 1.52 (1.41, 1.63) | 1.55 (1.41, 1.65) | 0.56 (0.52, 0.60) | 0.56 (0.52, 0.61) | ||||
| ≥0.29 μmol/g creatinine | 234 | 1.80 (1.66, 1.93) | 1.79 (1.66, 1.95) | 0.59 (0.55, 0.64) | 0.59 (0.55, 0.65) | ||||
| Polyphenol metabolites | |||||||||
| 4′-MeEGC | 0.21 | 0.45 | 0.52 | 0.25 | |||||
| 0 μmol/g creatinine4 | 334 | 1.66 (1.55, 1.77) | 1.68 (1.57, 1.80) | 0.57 (0.54, 0.61) | 0.58 (0.55, 0.62) | ||||
| >0–0.03 μmol/g creatinine | 131 | 1.60 (1.45, 1.76) | 1.60 (1.45, 1.79) | 0.54 (0.50, 0.60) | 0.54 (0.49, 0.60) | ||||
| >0.03 μmol/g creatinine | 235 | 1.58 (1.46, 1.72) | 1.62 (1.49, 1.75) | 0.58 (0.54, 0.63) | 0.58 (0.53, 0.62) | ||||
| 5-(3′,4',5′-rihydroxyphenyl)-γ-Valerolactone | 0.84 | 0.27 | 0.28 | 0.30 | |||||
| 0 μmol/g creatinine4 | 493 | 1.57 (1.49, 1.66) | 1.62 (1.52, 1.70) | 0.56 (0.54, 0.59) | 0.57 (0.54, 0.60) | ||||
| >0–0.004 μmol/g creatinine | 104 | 1.72 (1.55, 1.90) | 1.73 (1.55, 1.91) | 0.59 (0.55, 0.65) | 0.61 (0.54, 0.67) | ||||
| >0.004 μmol/g creatinine | 103 | 1.88 (1.57, 2.05) | 1.68 (1.45, 1.95) | 0.52 (0.45, 0.59) | 0.54 (0.47, 0.62) | ||||
| 5-(3′,4′-dihydroxyphenyl)-γ-Valerolactone | 0.62 | 0.95 | 0.14 | 0.18 | |||||
| <0.89 μmol/g creatinine | 233 | 1.57 (1.45, 1.72) | 1.58 (1.46, 1.72) | 0.59 (0.55, 0.64) | 0.60 (0.55, 0.64) | ||||
| 0.89–7.91 μmol/g creatinine | 233 | 1.62 (1.49, 1.73) | 1.65 (1.52, 1.79) | 0.55 (0.52, 0.59) | 0.60 (0.51, 0.59) | ||||
| >7.91 μmol/g creatinine | 234 | 1.70 (1.57, 1.84) | 1.70 (1.57, 1.86) | 0.56 (0.52, 0.60) | 0.57 (0.53, 0.62) | ||||
| Flavonoid polyphenols | |||||||||
| Kaempferol | 0.59 | 0.72 | 0.33 | 0.29 | |||||
| <0.04 μmol/g creatinine | 228 | 1.60 (1.48, 1.72) | 1.58 (1.46, 1.73) | 0.54 (0.51, 0.58) | 0.55 (0.51, 0.60) | ||||
| 0.04–0.28 μmol/g creatinine | 236 | 1.60 (1.48, 1.73) | 1.65 (1.52, 1.79) | 0.55 (0.52, 0.59) | 0.56 (0.52, 0.59) | ||||
| >0.28 μmol/g creatinine | 236 | 1.68 (1.55, 1.80) | 1.70 (1.55, 1.84) | 0.61 (0.56, 0.65) | 0.61 (0.56, 0.65) | ||||
| Quercetin | 0.06 | 0.01 | 0.24 | 0.03 | |||||
| <0.06 μmol/g creatinine | 217 | 1.46 (1.35, 1.58) | 1.51 (1.39, 1.65) | 0.54 (0.51, 0.59) | 0.54 (0.50, 0.58) | ||||
| 0.06–0.25 μmol/g creatinine | 249 | 1.63 (1.52, 1.77) | 1.63 (1.52, 1.77) | 0.55 (0.52, 0.59) | 0.56 (0.52, 0.60) | ||||
| >0.25 μmol/g creatinine | 234 | 1.77 (1.63, 1.93) | 1.79 (1.65, 1.93) | 0.61 (0.56, 0.65) | 0.61 (0.57, 0.66) | ||||
P values were from ANOVA for variables with 2 categories, and P-trend values were from a linear regression model for variables with >2 categories. F2-IsoP, F2-isoprostane; 4′-MeEGC, methylated form of epigallocatechin; 15-F2t-IsoP-M, 2,3-dinor-5,6-dihydro-15-F2t-isoprostane.
ANOVA estimate: values of log-transformed F2-IsoPs and their major metabolite 15-F2t-IsoP-M were adjusted for age (continuous); education; occupation; cigarette smoking (yes or no); BMI (continuous); multivitamin supplement use (yes or no); fruit and vegetable intakes (continuous); plasma total carotenoids, tocopherols, and retinol (continuous); and batch assays for F2-IsoPs or 15-F2t-IsoP-M (categories) and urinary tea polyphenols.
Geometric mean; 95% CI in parentheses (all such values).
The limits of detection for epicatechin, epigallocatechin, kaempferol, and quercetin are 1 nmol/L, whereas the limits of detection for polyphenol metabolites are 100 nmol/L.