Plasma concentrations of phyto-oestrogens in Japanese men

Lancet. 1993 Nov 13;342(8881):1209-10. doi: 10.1016/0140-6736(93)92188-y.


A low mortality from prostatic cancer is found in Japanese men consuming a low-fat diet with high content of soy products, a rich source of isoflavonoids. We therefore assayed four isoflavonoids in plasma of 14 Japanese and 14 Finnish men. The geometric mean plasma total individual isoflavonoid levels were 7 to 110 times higher in the Japanese than in the Finnish men. Genistein, a tyrosine kinase inhibitor, occurred in the highest concentration (geometric mean 276 nmol/L). We hypothesise that these high phyto-oestrogen levels may inhibit the growth of prostatic cancer in Japanese men, which may explain the low mortality from prostatic cancer in that country.

Publication types

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

MeSH terms

  • Chromans / blood
  • Diet
  • Equol
  • Estrogens, Non-Steroidal / blood*
  • Finland
  • Genistein
  • Humans
  • Isoflavones / blood*
  • Japan
  • Male
  • Middle Aged
  • Prostatic Neoplasms / etiology
  • Prostatic Neoplasms / mortality
  • Prostatic Neoplasms / prevention & control
  • Risk Factors


  • 4',7-dihydroxy-3,4-dihydroisoflavone
  • Chromans
  • Estrogens, Non-Steroidal
  • Isoflavones
  • Equol
  • daidzein
  • Genistein
  • O-desmethylangolensin