TABLE 2.

Plasma concentrations of isoflavones at baseline and 6 and 24 h postintervention in non-EPs and EPs after intake of placebo or isoflavone (80 mg isoflavone as aglycone equivalents)¹

	Intervention, nmol/L
	Placebo			Isoflavone supplement			P
EP phenotype and isoflavone	0 h	6 h	24 h	0 h	6 h	24 h	6 h	24 h
Non-EPs
Genistein	4 ± 3	15 ± 9	7 ± 5	4 ± 3	301 ± 40	72 ± 37	<0.0001	0.093
Daidzein	4 ± 2	16 ± 7	8 ± 4	4 ± 2	1692 ± 269	170 ± 46	<0.0001	0.002
S-equol	ND	ND	ND	ND	ND	ND	NA	NA
Glycitein	21 ± 7	20 ± 13	3 ± 2	21 ± 7	291 ± 48	54 ± 12	<0.0001	<0.0001
EPs
Genistein	ND	ND	3 ± 3	ND	200 ± 33	28 ± 15	<0.0001	0.11
Daidzein	1 ± 1	3 ± 2	4 ± 2	1 ± 1	1688 ± 215	190 ± 31	<0.0001	<0.0001
S-equol	ND	ND	ND	ND	ND	236 ± 81	NA	0.007
Glycitein	19 ± 6	7 ± 4	6 ± 4	19 ± 6	237 ± 36	35 ± 9	<0.0001	0.009

¹Values are means ± SEMs; n = 14/group. P values represent the differences (by using ANOVA) in circulating concentrations of isoflavones and equol between the isoflavone supplement and placebo groups at 6 and 24 h after treatment. Isoflavone concentrations were significantly greater at 6 and 24 h after the isoflavone supplement in EPs and non-EPs (P < 0.05 for all, except for genistein at 24 h and glycitein at 24 h in EPs; see Supplemental Table 2). Conversely, there were no significant differences at either 6 or 24 h after consumption of placebo in EPs or non-EPs (P > 0.05 for all; see Supplemental Table 3). EP, equol producer; NA, not applicable; ND, nondetectable or below the limit of detection.