Editing Equol (section)

===Pharmacokinetics===
(''S'')-Equol is a very stable molecule that essentially remains unchanged when digested, and this lack of further metabolism explains its very quick [[Absorption (pharmacology)|absorption]] and high [[bioavailability]].<ref>{{cite journal|last=Setchell|first=KD|author2=Zhao, X |author3=Jha, P |author4=Heubi, JE |author5=Brown, NM |title=The pharmacokinetic behavior of the soy isoflavone metabolite S-(-)equol and its diastereoisomer R-(+)equol in healthy adults determined by using stable-isotope-labeled tracers |journal=[[The American Journal of Clinical Nutrition]]|date=Oct 2009|volume=90|issue=4|pages=1029–37|pmid=19710188|doi=10.3945/ajcn.2009.27981|pmc=2744624}}</ref>
When (''S'')-equol is consumed, it is rapidly absorbed and achieves a T<sub>max</sub> (rate of [[peak plasma concentration]]) in two to three hours. In comparison, the T<sub>max</sub> of daidzein is 4 to 10 hours because daidzein exists in [[glycoside]] (with a glucose side chain) form. The body must convert daidzein to its [[aglycone]] form (without the glucose side chain) via removal of the sugar side chain during digestion before it can use daidzein.  If consumed directly in aglycone form, daidzein has a T<sub>max</sub> of one to three hours.<ref>{{cite journal|last=Setchell|first=KD|author2=Zhao, X |author3=Shoaf, SE |author4=Ragland, K |title=The pharmacokinetics of S-(-)equol administered as SE5-OH tablets to healthy postmenopausal women |journal=The Journal of Nutrition|date=Nov 2009|volume=139|issue=11|pages=2037–43|pmid=19776178|doi=10.3945/jn.109.110874|doi-access=free}}</ref>
The percent fractional elimination of (''S'')-equol in urine after oral administration is high and in some adults can reach close to 100 percent. The percent fractional elimination of daidzein is much lower at 30 to 40 percent.<ref>{{cite journal|last=Setchell|first=KD|author2=Clerici, C |title=Equol: pharmacokinetics and biological actions |journal=The Journal of Nutrition|date=Jul 2010|volume=140|issue=7|pages=1363S–8S|pmid=20519411|doi=10.3945/jn.109.119784|pmc=2884334}}</ref>