Applied nutritional investigation Lack of effects of isoﬂavones on the lipid proﬁle of Brazilian postmenopausal women Danyelle Romana A. Rios, M.D. a , Edna T. Rodrigues, M.D. a , Ana Paula Z. Cardoso, B.Sc. a , Marlise Boneti A. Montes, B.Sc. a , Sílvio A. Franceschini, M.D. b , and Maria Regina T. Toloi, M.D. a, * a Department of Clinical, Toxicological and Bromatological Analysis, Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil b University of Ribeirao Preto, UNAERP, Ribeirao Preto, Sao Paolo, Brazil Manuscript received March 29, 2008; accepted June 19, 2008. Abstract Objective: To evaluate the effects of soy isoﬂavone supplementation on proﬁle lipid and endog- enous hormone levels. Methods: In this double-blind, placebo-controlled study, 47 postmenopausal women 47– 66 y of age received 40 mg of isoﬂavone (n  25) or 40 mg of casein placebo (n  22). Cardiovascular risk factors were assessed by evaluating lipid proﬁle at baseline and after 6 mo of treatment. To examine the effects of this regime on endogenous hormone levels, follicle-stimulating hormone and -estradiol were measured. Urinary isoﬂavone concentrations (genistein and daidzein) were measured as markers of both compliance and absorption using high performance liquid chromatography. Base- line characteristics were compared by the unpaired Student’s t-test. Within-group changes were determined by paired Student’s t-test and comparison between the isoﬂavone and casein placebo groups were determined by analysis of variance. Results: Lipid levels (low-density lipoprotein and total cholesterol) similarly decreased in both groups. High-density lipoprotein increased signiﬁcantly in both groups and cannot thus be attrib- utable to treatment; the reason for such variation is unknown and can be attributed to chance or to bias (even that of a real placebo effect in both groups or perhaps in spontaneous changes in exercise and dietary habits of patients after their inclusion). Furthermore, in both groups very low-density lipoprotein and triacylglycerol levels increased in a non-signiﬁcant manner. Conclusion: The results of the present study do not support any biologically signiﬁcant estrogenic effects of isoﬂavone on the parameters assessed. Further research will be necessary to deﬁnitively assess the safety and efﬁcacy of isoﬂavone. © 2008 Elsevier Inc. All rights reserved. Keywords: Lipids; Sex hormones; Soy isoﬂavone; Postmenopausal women Introduction Menopause is deﬁned by the World Health Organization as the permanent cessation of menstrual periods that occurs naturally or is induced by surgery, chemotherapy, or radia- tion. The characteristic symptoms in the postmenopausal period are hot ﬂashes, sweats, dyspareunia, urogenital atro- phies, and depression [1]. After menopause, the incidence of cardiovascular disease increases in women, a fact possibly related to the decrease in estrogen levels after menopause. Hormone replacement therapy (HRT) usually involves es- trogen combined with progestogen and has the objective of treating the symptoms of menopause and preventing osteo- porosis, in a way to increase the quality of postmenopausal women’s life. Studies have raised concerns about an early adverse effect of HRT on cardiovascular risk [2,3]. HRT is able to reverse, at least in part, the postmenopausal increase in total cholesterol and low-density lipoprotein (LDL) and the decrease in high-density lipoprotein (HDL). However, in This word was ﬁnancially by the FAPESP and CAPES/BRAZIL. * Corresponding author. Tel.: 55-16-3602-4220/4208; fax: 55-16- 3602-4725. E-mail address: torqueti@fcfrp.usp.br (M. R. T. Toloi). Nutrition 24 (2008) 1153–1158 www.elsevier.com/locate/nut 0899-9007/08/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.nut.2008.06.030