Micronutrients, nutraceutics and functional foodsSkeletal benefits of soy isoflavones: a review of the clinical trial and epidemiologic dataMessina, Marka; Ho, Suzanneb; Alekel, D LeecAuthor Information aDepartment of Nutrition, School of Public Health, Loma Linda University, Loma Linda, California, USA, bDepartment of Community and Family Medicine, Centre of Research and Promotion of Women's Health, School of Public Health, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, SAR and cHuman Metabolic Unit, Center for Designing Foods to Improve Nutrition, Iowa State University, Ames, Iowa, USA Correspondence to Mark Messina, Department of Nutrition, School of Public Health, Loma Linda University, Loma Linda, California, USA Tel: +1 360 379 9544; fax: +1360 379 9614; e-mail: [email protected] Abbreviations BMC: bone mineral content BMD: bone mineral density Current Opinion in Clinical Nutrition and Metabolic Care: November 2004 - Volume 7 - Issue 6 - p 649-658 Buy Abstract Purpose of review Osteoporosis is a worldwide problem of immense magnitude that is expected to worsen in many countries with aging populations. Consequently, there is a need to identify ways to reduce the risk of developing this disease. This is especially true in light of clinical trial data showing the long-term harm of conventional hormone therapy outweighs the benefits. It is well established that many dietary components impact the skeletal system; in this regard there is particular interest in the possible skeletal benefits of soybean isoflavones. The purpose of this review is to evaluate the clinical and epidemiologic studies relevant to the hypothesis that isoflavones promote bone health. Results Fifteen clinical trials were identified that examined the effects of isoflavones or isoflavone-rich soy protein on bone mineral density. Most trials were conducted for 1 year or less and involved relatively few (<30) participants per group. The findings from these studies are inconsistent but generally suggest that isoflavones reduce bone loss in younger postmenopausal women. Similarly, the limited epidemiologic data generally show that among Asian populations isoflavone intake is associated with higher bone mineral density. The clinical data suggest that approximately 80 mg/day isoflavones are needed to derive skeletal benefits whereas the epidemiologic data suggest lower amounts are efficacious. Summary Until more definite data are available, although soy foods and isoflavones can not be viewed as substitutes for established anti-osteoporotic medications health professionals can feel justified in encouraging postmenopausal women concerned about bone health to incorporate soyfoods into their diet. © 2004 Lippincott Williams & Wilkins, Inc.