Table 3
Age standardized geometric means for urinary concentrations of estrogens and estrogen metabolites (EM) and multivariable-adjusted percent difference1across categories of green tea intake in premenopausal women during the luteal phase
	Categories of green tea intake
	<1 per week (n = 62)	1-6 times per week (n = 32)		7+ times per week (n = 25)
	Urinary concentration	Urinary concentration	Percent difference	Urinary concentration	Percent difference	Ptrend
Total Estrogens and Metabolites	218.16	156.13	−25.5% (-40.7%--6.4%)	170.36	−26.3% (-43.0%--4.6%)	0.01
Parent Estrogens	37.58	29.99	−16.0% (-35.2%-8.9%)	34.57	−8.1% (-31.7%-23.6%)	0.42
Estrone	24.45	19.44	−20.2% (-39.2%-4.8%)	23.07	−6.9% (-31.8%-27.2%)	0.43
Estradiol	11.53	10.01	−5.4% (-27.0%-22.5%)	10.28	−8.9% (-32.1%-22.3%)	0.51
2-Hydroxylation pathway	39.11	28.05	−36.9% (-52.3%--16.4%)	38.11	−16.2%(-39.5%-16.0%)	0.10
2-Pathway catechols	30.57	22.42	−38.3%(-54.2%--16.8%)	28.5	−16.9%(-41.2%-17.6%)	0.10
2-Hydroxyestrone	27.65	19.68	−38.8%(-54.6%--17.6%)	27.06	−16.3%(-40.7%-18.2%)	0.10
2-Hydroxyestradiol	3.02	1.90	−43.9%(-61.9%--17.3%)	2.61	−25.5% (-52.4%-16.5%)	0.07
2-Pathway methylated catechols	7.24	5.66	−28.9%(-47.7%--3.5%)	7.77	−9.6%(-36.3%-28.2%)	0.34
2-Methoxyestrone	5.17	4.18	−24.0% (-44.6%-4.2%)	5.74	−1.3%(-31.4%-41.9%)	0.67
2-Methoxyestradiol	0.56	0.41	−28.7% (-50.8%-3.3%)	0.64	0.6% (-34.0%-53.4%)	0.73
2-Hydroxyestrone-3-methyl ether	1.15	0.81	−34.1% (-56.3%--0.5%)	1.06	−22.9%(-51.5%-22.5%)	0.17
4-Hydroxylation pathway EM	4.13	3.32	−21.4% (-43.3%-8.9%)	3.80	−13.5% (-40.3%-25.3%)	0.33
4-Pathway catechol: 4-Hydroxyestrone	3.71	2.95	−21.9% (-44.3%-9.6%)	3.31	−15.5% (-42.4%-24.1%)	0.29
4-Pathway methylated catechols	0.33	0.28	−19.1% (-43.3%-15.3%)	0.36	−7.1% (-38.0%-39.2%)	0.53
4-Methoxyestrone	0.23	0.17	−23.9% (-48.1%-11.6%)	0.24	4.0% (-32.5%-60.4%)	0.93
4-Methoxyestradiol	0.05	0.06	−15.2% (-56.1%-63.6%)	0.08	−8.2% (-56.4%-93.4%)	0.77
16-Hydroxylation pathway	123.03	84.72	−21.3% (-39.7%-2.7%)	87.57	−33.3% (-50.3% --10.4%)	0.001
16α-Hydroxyestrone	12.68	9.31	−24.0%(-40.9%--2.3%)	9.78	−31.1% (-48.2%--8.5%)	0.01
Estriol	68.67	44.67	−23.5% (-43.2%-2.9%)	46.16	−33.1% (-51.9%--7.0%)	0.01
16-Ketoestradiol	25.68	19.98	−17.8% (-39.8%-12.2%)	19.32	−31.5% (-51.3%--3.7%)	0.02
16-Epiestriol	10.09	7.11	−15.1% (-36.6%-13.6%)	7.74	−30.8% (-49.9%--4.2%)	0.02
17-Epiestriol	1.79	0.97	−27.4% (-54.9%-16.8%)	0.95	−40.4% (-65.1%-1.7%)	0.04
Ratios
Parent estrogens / estrogen metabolites	0.21	0.24	10.6% (-11.5%-38.3%)	0.26	23.1% (-3.8%-57.6%)	0.09
2-Hydroxylation pathway / parent estrogens	1.04	0.94	−19.3% (-37.3%-3.8%)	1.10	−9.5% (-31.7%-20.1%)	0.37
4-Hydroxylation pathway / parent estrogens	0.11	0.11	−9.9% (-32.9%-21.2%)	0.11	−15.8% (-39.2%-16.6%)	0.28
16-Hydroxylation pathway / parent estrogens	3.27	2.83	−5.1% (-27.8%-24.8%)	2.53	−20.0% (-41.0%-8.5%)	0.17
2-Hydroxylation pathway / 16-hydroxylation pathway	0.32	0.33	−3.7% (-33.2%-38.8%)	0.44	21.2% (-19.8%-83.0%)	0.41
4-Hydroxylation pathway / 16-hydroxylation pathway	0.03	0.04	16.8% (-21.3%-73.3%)	0.04	21.8% (-21.8%-89.8%)	0.34
2-Hydroxylation pathway / 4-hydroxylation pathway	9.47	8.46	−13.3% (-28.3%-4.7%)	10.04	−1.2% (-20.2%-22.4%)	0.70
4-Pathway methylated catechols / 4-pathway catechols	0.09	0.09	20.7% (-13.4%-68.1%)	0.11	23.9% (-15.2%-81.0%)	0.20
2-Pathway methylated catechols / 2-pathway catechols	0.23	0.26	9.1% (-11.6%-34.6%)	0.26	7.7% (-15.1%-36.7%)	0.48

Derived measures of estrogen metabolism and statistically significant estimates are presented in bold font.

¹ Robust linear regression models were used to estimate percent difference in EM measures with 95% confidence limits across categories of green tea intake while adjusting for age and study center.

² Robust linear regression was used to test for trends in log-transformed EM measures across tea categories. P_trend was modeled using categories coded as 0, 1, and 2.

Fuhrman et al. Nutrition Journal 2013 12:25   doi:10.1186/1475-2891-12-25