Supplementation with isoflavonoid phytoestrogens does not alter serum lipid concentrations: a randomized controlled trial in humans

• Published in: The Journal of nutrition Vol. 128; no. 4; pp. 728 - 732
• Main Authors: Hodgson, J.M. (University of Western Australia, Perth, WA, Australia.), Puddey, I.B, Beilin, L.J, Mori, T.A, Croft, K.D
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Nutritional Sciences 01.04.1998; American Institute of Nutrition
• Subjects: Adult; Aged; Biological and medical sciences; BLOOD LIPIDS; BLOOD SERUM; Body Weight; CHOLESTEROL; CLINICAL TRIALS; COLESTEROL; COMPLEMENT ALIMENTAIRE; DAIDZEIN; DIET; DIETA; Dietary Supplements; Double-Blind Method; ENSAYOS CLINICOS; ESSAI CLINIQUE; ESTROGENOS; Estrogens, Non-Steroidal - pharmacology; Feeding. Feeding behavior; Female; FEMME; FLAVONOIDE; FLAVONOIDES; FLAVONOIDS; FORMONONETIN; Fundamental and applied biological sciences. Psychology; GENISTEIN; HEMOLIPIDOS; HIGH DENSITY LIPOPROTEIN; HOMBRES; HOMME; Humans; ISOFLAVONES; Isoflavones - pharmacology; Isoflavones - urine; LIPIDE SANGUIN; Lipids; Lipids - blood; LIPOPROTEIN (A); LIPOPROTEINAS; LIPOPROTEINE; LIPOPROTEINS; Lipoproteins - blood; LOW DENSITY LIPOPROTEIN; Male; MEN; Middle Aged; MUJERES; Nutrition; O-DESMETHYLANGOLENSIN; OESTROGENE; OESTROGENS; Osmolar Concentration; Phytoestrogens; Plant Preparations; REGIME ALIMENTAIRE; SERUM SANGUIN; SUERO SANGUINEO; SUPLEMENTOS; SUPPLEMENTS; TRIGLICERIDOS; TRIGLYCERIDE; TRIGLYCERIDES; Vertebrates: anatomy and physiology, studies on body, several organs or systems; WOMEN; Human; Nutrition; Estrogen; Plant origin; Lipids; Sex steroid hormone; Isoflavone derivatives; Ovarian hormone; Food supplement; Blood plasma
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/128.4.728

Isoflavonoids are a class of flavonoids that are derived in the human diet mainly from soybean-based foods. The major dietary isoflavonoids, genistein and daidzein, have estrogen-like activity and are classed as phytoestrogens. Because estrogens can lower serum LDL cholesterol and raise HDL cholesterol, the objective of this study was to determine if isoflavonoids could improve serum lipids in healthy subjects. Forty-six men and 13 postmenopausal women not receiving hormone replacement therapy completed a randomized, double-blind, placebo-controlled trial of two-way parallel design and 8 wk duration. One tablet containing 55 mg of isoflavonoids (predominantly in the form of genistein) or one placebo tablet was taken daily with the evening meal. Subjects maintained their usual diet and physical activity, which were unchanged throughout the intervention. Measurement of isoflavonoids and their metabolites in 24-h urine samples provided an assessment of compliance and of isoflavonoid metabolism. Serum total, LDL, HDL and HDL subclass cholesterol, triglycerides and lipoprotein (a) were assessed at baseline and during the last week of intervention. After adjustment for baseline values, no significant differences in postintervention serum lipid and lipoprotein (a) concentrations between groups were identified. Further adjustment for age, gender and weight change did not alter the results. In addition, changes in urinary isoflavonoids were not significantly correlated with changes in serum lipids and lipoprotein (a). Therefore, this study does not support the hypothesis that isoflavonoid phytoestrogens can improve the serum lipids, at least in subjects with average serum cholesterol concentrations