Preventive effects of phytoestrogens against postmenopausal osteoporosis as compared to the available therapeutic choices: An overview

Estrogen deficiency is a major risk factor for osteoporosis in postmenopausal women. Although hormone replacement therapy (HRT) has been rampantly used to recompense for the bone loss, but the procedure is coupled with severe adverse effects. Hence, there is a boost in the production of newer synthetic products to ward off the effects of menopause-related osteoporosis. As of today, there are several prescription products available for the treatment of postmenopause osteoporosis; most of these are estrogenic agents and combination products. Nevertheless, in view of the lack of effect and/or toxicity of these products, majority of the postmenopausal women are now fascinated by highly publicized natural products. This is an offshoot of the generalized consensus that these products are more effective and free from any adverse effects. Recently, certain plant-derived natural products, mostly phytoestrogens (isoflavones, lignans, coumestanes, stilbenes, flavonoids) and many more novel estrogen-like compounds in plants have been immensely used to prevent menopause-related depletion in bone mineral density (BMD). Although, a number of papers are published on menopause-related general symptoms, sexual dysfunction, cardiovascular diseases, Alzheimer's disease, diabetes, colon, and breast cancers, there is paucity of literature on the accompanying osteoporosis and its treatment. In view of the controversies on synthetic hormones and drugs and drift of a major population of patients toward natural drugs, it was found worthwhile to investigate if these drugs are suitable to be used in the treatment of postmenopausal osteoporosis. Preparation of this paper is an attempt to review the (a) epidemiology of postmenopausal osteoporosis, (b) treatment modalities of postmenopausal osteoporosis by hormones and synthetic drugs and the associated drawbacks and adverse effects, and (c) prevention and treatment of postmenopausal osteoporosis by phytoestrogens, their drawbacks and toxicity. It is apparent that both the categories of treatment are useful and both have adverse effects, but the plant products are nonscientific and hence are not advised to be used till more studies are undertaken to ensure that the benefits clearly outweigh the risk, in addition to recognition by Food and Drug Administration.