Urinary lignan and isoflavonoid excretion in men and women consuming vegetable and soy diets

Nutr Cancer. 1995;24(1):1-12. doi: 10.1080/01635589509514388.


Urinary lignan and isoflavonoid excretion were examined in 11 men and 9 women consuming four nine-day controlled experimental diets: basal (vegetable free), carotenoid vegetable (carrot and spinach), cruciferous vegetable (broccoli and cauliflower), and soy (tofu and textured vegetable protein product). Three-day urine collections (Days 7-9) were analyzed for lignans and isoflavonoids with use of isotope-dilution gas chromatography-mass spectrometry. Urinary excretion of the lignans enterodiol and enterolactone was higher during the carotenoid and cruciferous vegetable diets than during the basal diet (p = 0.0001), suggesting that these vegetables may provide a source of mammalian lignan precursors. Urinary excretion of the isoflavonoids equol, O-desmethylangolensin, daidzein, and genistein was higher when subjects consumed soy diets than when they consumed the other test diets (p < 0.02). Gender differences in lignan excretion were observed. Men excreted more enterolactone (p = 0.006) and less enterodiol (p = 0.013) than women, implying a gender difference in colonic bacterial metabolism of lignans. There was no effect of gender on isoflavonoid excretion.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 4-Butyrolactone / analogs & derivatives
  • 4-Butyrolactone / urine
  • Adult
  • Chromans / urine
  • Colon / metabolism
  • Colon / microbiology
  • Cross-Over Studies
  • Diet / standards*
  • Equol
  • Female
  • Gas Chromatography-Mass Spectrometry
  • Genistein
  • Humans
  • Isoflavones / urine*
  • Lignans / urine*
  • Male
  • Sex Characteristics
  • Soybeans / standards*
  • Vegetables / standards*


  • 4',7-dihydroxy-3,4-dihydroisoflavone
  • Chromans
  • Isoflavones
  • Lignans
  • Equol
  • daidzein
  • 2,3-bis(3'-hydroxybenzyl)butane-1,4-diol
  • Genistein
  • 4-Butyrolactone
  • 2,3-bis(3'-hydroxybenzyl)butyrolactone