title: Phytoestrogen concentrations in serum from Japanese men and women over forty years of age.
abstract: Asian individuals have much lower incidences of prostate and breast cancer than populations from Western developed countries. They also consume a lower fat, higher fiber diet, with a large intake of phytoestrogens. These phytoestrogens may protect against hormone-dependent cancers and other diseases. Our study used established gas chromatography-mass spectrometry (GC-MS) methodologies to measure the concentrations of four phytoestrogens (daidzein, genistein, equol and enterolactone) in serum samples obtained from Japanese men (n = 102) and women (n = 125) > 40 y old. The results were compared with those obtained with samples from the UK. The Japanese men and women had higher (P < 0.001) concentrations of circulating daidzein, genistein and equol than individuals from the UK. The mean concentration of genistein in Japanese men, for example, was 492.7 nmol/L, compared with 33.2 nmol/L in men from the UK. The two populations, however, had similar serum concentrations of enterolactone. Furthermore, 58% of the Japanese men and 38% of the Japanese women had equol concentrations > 20 nmol/L, compared with none of the UK men and 2.2% of the UK women. These results support previously published GC-MS results from studies with low numbers of samples.
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000097:blood; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D002839:Chromans / Q000097:blood; D004032:Diet; D060754:Equol; D004968:Estrogens, Non-Steroidal / Q000008:administration & dosage / Q000097:blood*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D019833:Genistein / Q000097:blood; D006801:Humans; D007529:Isoflavones / Q000097:blood; D007564:Japan; D017705:Lignans / Q000097:blood; D008297:Male; D008875:Middle Aged; D048789:Phytoestrogens; D028321:Plant Preparations; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology / Q000517:prevention & control; D006113:United Kingdom
chemical_list: C007610:4',7-dihydroxy-3,4-dihydroisoflavone; D002839:Chromans; D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; D017705:Lignans; D048789:Phytoestrogens; D028321:Plant Preparations; D060754:Equol; C004742:daidzein; D019833:Genistein; D015107:4-Butyrolactone; C029497:2,3-bis(3'-hydroxybenzyl)butyrolactone