biochanin-enriched isoflavone from red clover lowers LDL cholesterol in men

• Published in: European journal of clinical nutrition Vol. 58; no. 3; pp. 403 - 408
• Main Authors: Nestel, P, Cehun, M, Chronopoulos, A, DaSilva, L, Teede, H, McGrath, B
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.03.2004; Nature Publishing; Nature Publishing Group
• Subjects: Aged; Analysis of Variance; Anticholesteremic Agents - pharmacology; Biological and medical sciences; blood lipids; cholesteremic effect; Cholesterol; Cholesterol, LDL - blood; Clinical Nutrition; Cross-Over Studies; Crossovers; Daidzein; Design; Dietary Supplements; Double-Blind Method; Enrichment; Epidemiology; Female; formononetin; Genistein; Genistein - pharmacology; Humans; Internal Medicine; Isoflavones; Isoflavones - pharmacology; Lipids; Low density lipoprotein; low density lipoprotein cholesterol; Male; Medical sciences; Medicine; Medicine & Public Health; Men; Metabolic Diseases; Middle Aged; Miscellaneous; Nutrients; original-communication; Placebos; Post-menopause; Postmenopause; Precursors; Public Health; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Red clover; Sex Factors; Treatment Outcome; Trifolium - chemistry; Trifolium pratense; Variance analysis; volunteers; women; red clover; isoflavones; LDL cholesterol; formononetin; biochanin; Isoflavone; Middle age; Genistein; Cholesterol LDL; Lipoprotein a; Lipoprotein LDL; Randomization; Treatment; Diet; Double blind study; Postmenopause; Female; Comparative study
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1601796

Objective: To determine whether the two major isoflavones in red clover differ in their effect on low-density lipoprotein cholesterol (LDL-C). Design: A randomised, placebo-controlled, double-blind trial; two parallel groups taking one of the two isoflavones within which treatment and placebo were administered in a crossover design. Setting: Free-living volunteers. Subjects: A total of 46 middle-aged men and 34 postmenopausal women. Intervention: Two mixtures of red clover isoflavones enriched in either biochanin (n=40) or formononetin (n=40) were compared. Placebo and active treatment (40 mg/day) were administered for 6 weeks each in a crossover design within the two parallel groups. Main outcome measures: Plasma lipids were measured twice at the end of each period. Results: Baseline LDL-C concentrations did not differ significantly between men (n=46) and women (n=34), nor between those randomised to biochanin or formononetin. Interaction between time and treatments, biochanin, formononetin and corresponding placebos (two-way ANOVA) on LDL-C showed a significant effect of biochanin treatment alone. The biochanin effect was confined to men; median LDL-C was 3.61 (3.05-4.14) mmol/l with biochanin and 3.99 (3.16-4.29) mmol/l with the corresponding placebo (RM ANOVA with Dunnett's adjustment P<0.05). The difference between placebo and biochanin effects on LDL-C was 9.5%. No other lipid was affected and women failed to respond significantly to treatment. Conclusion: Isolated isoflavones from red clover enriched in biochanin (genistein precursor) but not in formononetin (daidzein precursor), lowered LDL-C in men. This may partly explain the previous failure to demonstrate cholesterol-lowering effects with mixed isoflavones studied predominantly in women.