Determinants for urinary and plasma isoflavones in humans after soy intake

Adrian A. Franke, Laurie J. Custer, Scott A Hundahl

Research output: Contribution to journalArticle

56 Citations (Scopus)

Abstract

Consumption of soy foods leads to a biphasic appearance pattern of isoflavones (IFLs) in blood and urine, with peaks appearing at 1-2 h and 4-8 h after intake, but its causes are not understood. IFLs were measured repeatedly from plasma and/or urine after intake of soy foods, IFL glucosides, or aglycons without or with a mildly or radically reduced gut flora as a result of oral antibiotic (AB) treatment, or this combined with mechanical bowel preparation (AB+MBP). The typical biphasic IFL pattern in blood and/or urine was observed when a soy protein drink without (control) or with AB treatment or when IFL glucosides or aglycons were consumed. Soy intake combined with AB+MBP or consumption of puerarin led to a shift of the second peak to much later times. The first peak was absent after puerarin intake. Total urinary IFL recovery was more than 50% lower in the first 24 h, but overall 61% higher after AB+MBP vs. the control. When the area under the curves for corresponding time intervals were compared, individual or total urinary IFL excretion rates were highly correlated with individual or total plasma IFL levels (r = 0.85-0.91; P < 0.001). At the same urinary excretion rate three times more genistein than daidzein remained in the circulation. We conclude that urinary IFL excretion rates reflect circulating IFL levels, with daidzein appearing less in blood and more in urine than genistein. The first and second IFL peaks are due to uptake in the small and large intestine, respectively. The latter is the major locus of uptake (90%) at usual dietary IFL doses (0.15-1.5 μmol/kg body weight). A reduced gut flora delayed IFL uptake but led overall to increased urinary recovery because of less bacterial degradation in the intestine.

Original languageEnglish (US)
Pages (from-to)141-154
Number of pages14
JournalNutrition and Cancer
Volume50
Issue number2
DOIs
StatePublished - 2004
Externally publishedYes

Fingerprint

Isoflavones
isoflavones
antibiotics
Anti-Bacterial Agents
urine
Urine
Soy Foods
daidzein
excretion
Genistein
genistein
Glucosides
uptake mechanisms
intestinal microorganisms
glucosides
blood
Soybean Proteins
Large Intestine
large intestine
soy protein

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Oncology
  • Food Science

Cite this

Determinants for urinary and plasma isoflavones in humans after soy intake. / Franke, Adrian A.; Custer, Laurie J.; Hundahl, Scott A.

In: Nutrition and Cancer, Vol. 50, No. 2, 2004, p. 141-154.

Research output: Contribution to journalArticle

Franke, Adrian A. ; Custer, Laurie J. ; Hundahl, Scott A. / Determinants for urinary and plasma isoflavones in humans after soy intake. In: Nutrition and Cancer. 2004 ; Vol. 50, No. 2. pp. 141-154.
@article{d86fd8a4a89643519dfdaf66a257560a,
title = "Determinants for urinary and plasma isoflavones in humans after soy intake",
abstract = "Consumption of soy foods leads to a biphasic appearance pattern of isoflavones (IFLs) in blood and urine, with peaks appearing at 1-2 h and 4-8 h after intake, but its causes are not understood. IFLs were measured repeatedly from plasma and/or urine after intake of soy foods, IFL glucosides, or aglycons without or with a mildly or radically reduced gut flora as a result of oral antibiotic (AB) treatment, or this combined with mechanical bowel preparation (AB+MBP). The typical biphasic IFL pattern in blood and/or urine was observed when a soy protein drink without (control) or with AB treatment or when IFL glucosides or aglycons were consumed. Soy intake combined with AB+MBP or consumption of puerarin led to a shift of the second peak to much later times. The first peak was absent after puerarin intake. Total urinary IFL recovery was more than 50{\%} lower in the first 24 h, but overall 61{\%} higher after AB+MBP vs. the control. When the area under the curves for corresponding time intervals were compared, individual or total urinary IFL excretion rates were highly correlated with individual or total plasma IFL levels (r = 0.85-0.91; P < 0.001). At the same urinary excretion rate three times more genistein than daidzein remained in the circulation. We conclude that urinary IFL excretion rates reflect circulating IFL levels, with daidzein appearing less in blood and more in urine than genistein. The first and second IFL peaks are due to uptake in the small and large intestine, respectively. The latter is the major locus of uptake (90{\%}) at usual dietary IFL doses (0.15-1.5 μmol/kg body weight). A reduced gut flora delayed IFL uptake but led overall to increased urinary recovery because of less bacterial degradation in the intestine.",
author = "Franke, {Adrian A.} and Custer, {Laurie J.} and Hundahl, {Scott A}",
year = "2004",
doi = "10.1207/s15327914nc5002_3",
language = "English (US)",
volume = "50",
pages = "141--154",
journal = "Nutrition and Cancer",
issn = "0163-5581",
publisher = "Routledge",
number = "2",

}

TY - JOUR

T1 - Determinants for urinary and plasma isoflavones in humans after soy intake

AU - Franke, Adrian A.

AU - Custer, Laurie J.

AU - Hundahl, Scott A

PY - 2004

Y1 - 2004

N2 - Consumption of soy foods leads to a biphasic appearance pattern of isoflavones (IFLs) in blood and urine, with peaks appearing at 1-2 h and 4-8 h after intake, but its causes are not understood. IFLs were measured repeatedly from plasma and/or urine after intake of soy foods, IFL glucosides, or aglycons without or with a mildly or radically reduced gut flora as a result of oral antibiotic (AB) treatment, or this combined with mechanical bowel preparation (AB+MBP). The typical biphasic IFL pattern in blood and/or urine was observed when a soy protein drink without (control) or with AB treatment or when IFL glucosides or aglycons were consumed. Soy intake combined with AB+MBP or consumption of puerarin led to a shift of the second peak to much later times. The first peak was absent after puerarin intake. Total urinary IFL recovery was more than 50% lower in the first 24 h, but overall 61% higher after AB+MBP vs. the control. When the area under the curves for corresponding time intervals were compared, individual or total urinary IFL excretion rates were highly correlated with individual or total plasma IFL levels (r = 0.85-0.91; P < 0.001). At the same urinary excretion rate three times more genistein than daidzein remained in the circulation. We conclude that urinary IFL excretion rates reflect circulating IFL levels, with daidzein appearing less in blood and more in urine than genistein. The first and second IFL peaks are due to uptake in the small and large intestine, respectively. The latter is the major locus of uptake (90%) at usual dietary IFL doses (0.15-1.5 μmol/kg body weight). A reduced gut flora delayed IFL uptake but led overall to increased urinary recovery because of less bacterial degradation in the intestine.

AB - Consumption of soy foods leads to a biphasic appearance pattern of isoflavones (IFLs) in blood and urine, with peaks appearing at 1-2 h and 4-8 h after intake, but its causes are not understood. IFLs were measured repeatedly from plasma and/or urine after intake of soy foods, IFL glucosides, or aglycons without or with a mildly or radically reduced gut flora as a result of oral antibiotic (AB) treatment, or this combined with mechanical bowel preparation (AB+MBP). The typical biphasic IFL pattern in blood and/or urine was observed when a soy protein drink without (control) or with AB treatment or when IFL glucosides or aglycons were consumed. Soy intake combined with AB+MBP or consumption of puerarin led to a shift of the second peak to much later times. The first peak was absent after puerarin intake. Total urinary IFL recovery was more than 50% lower in the first 24 h, but overall 61% higher after AB+MBP vs. the control. When the area under the curves for corresponding time intervals were compared, individual or total urinary IFL excretion rates were highly correlated with individual or total plasma IFL levels (r = 0.85-0.91; P < 0.001). At the same urinary excretion rate three times more genistein than daidzein remained in the circulation. We conclude that urinary IFL excretion rates reflect circulating IFL levels, with daidzein appearing less in blood and more in urine than genistein. The first and second IFL peaks are due to uptake in the small and large intestine, respectively. The latter is the major locus of uptake (90%) at usual dietary IFL doses (0.15-1.5 μmol/kg body weight). A reduced gut flora delayed IFL uptake but led overall to increased urinary recovery because of less bacterial degradation in the intestine.

UR - http://www.scopus.com/inward/record.url?scp=12744272008&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=12744272008&partnerID=8YFLogxK

U2 - 10.1207/s15327914nc5002_3

DO - 10.1207/s15327914nc5002_3

M3 - Article

C2 - 15623460

AN - SCOPUS:12744272008

VL - 50

SP - 141

EP - 154

JO - Nutrition and Cancer

JF - Nutrition and Cancer

SN - 0163-5581

IS - 2

ER -