title: Consumption of soy isoflavones does not affect plasma total homocysteine or asymmetric dimethylarginine concentrations in healthy postmenopausal women.
abstract: Postmenopausal women are at increased risk for cardiovascular disease because many risk factors are aggravated by menopause. Phytoestrogens may modulate risk factors favorably, involving mechanisms similar to estrogen. The effect of phytoestrogens on the atherogenic amino acids homocysteine and asymmetric dimethylarginine (ADMA) was investigated in a controlled intervention study in healthy postmenopausal women. A multicenter, double-blind, crossover intervention trial in 89 postmenopausal women from Denmark, Germany, and the UK was performed. Subjects consumed fruit cereal bars with or without soy isoflavones (50 mg/d) for 8 wk each with an 8-wk washout period in between. Urinary phytoestrogens increased significantly after isoflavone intervention (P < 0.001). Isoflavone supplementation did not affect plasma total homocysteine or ADMA. For homocysteine, changes from baseline were 0.32 micromol/L (range: -0.31-0.92; 95% CI 0.13-0.72), and 0.29 micromol/L (range: -0.45-1.09; 95% CI 0.01-0.63, P = 0.286) for isoflavone treatment and placebo, respectively. For ADMA concentrations, changes from baseline were -0.02 micromol/L (range: -0.08-0.03; 95% CI -0.04-0.01, and 0.00 micromol/L (range: -0.05-0.03; 95% CI -0.03-0.01, P = 0.397) for isoflavone treatment and placebo, respectively. There was no association between plasma total homocysteine and ADMA. Changes from baseline in plasma ADMA and folate were negatively correlated (r = -0.18, P = 0.017). These results challenge the overall health effect of isoflavone supplementation in healthy postmenopausal women.
authors.affiliation: German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany. reimann@mail.dife.de
authors.forename: Manja
authors.initials: M
authors.lastname: Reimann
authors.forename: Jutta
authors.initials: J
authors.lastname: Dierkes
authors.forename: Anja
authors.initials: A
authors.lastname: Carlsohn
authors.forename: Duncan
authors.initials: D
authors.lastname: Talbot
authors.forename: Marika
authors.initials: M
authors.lastname: Ferrari
authors.forename: Jesper
authors.initials: J
authors.lastname: Hallund
authors.forename: Wendy L
authors.initials: WL
authors.lastname: Hall
authors.forename: Katerina
authors.initials: K
authors.lastname: Vafeiadou
authors.forename: Ulrich
authors.initials: U
authors.lastname: Huebner
authors.forename: Francesco
authors.initials: F
authors.lastname: Branca
authors.forename: Susanne
authors.initials: S
authors.lastname: Bugel
authors.forename: Christine M
authors.initials: CM
authors.lastname: Williams
authors.forename: H-J Franz
authors.initials: HJ
authors.lastname: Zunft
authors.forename: Corinna
authors.initials: C
authors.lastname: Koebnick
mesh_terms: D000368:Aged; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D002784:Cholesterol / Q000097:blood; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005858:Germany; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007529:Isoflavones / Q000378:metabolism / Q000494:pharmacology*; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood; D030262:Soybean Proteins / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D007529:Isoflavones; D030262:Soybean Proteins; C487735:dimethylarginine; D006710:Homocysteine; D001120:Arginine; D002784:Cholesterol