The Secret of Soy,What is Soy Isoflavones?Function of Natural Genistein?Soy Bean Extract.

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Soy Isoflavones Prevent Osteoporosis.

Soy Bean Extract INCI Name Glycine Soja Extract Soy Isoflavones Genistein Daidzein CAS 84776-91-0 Genistein CAS 446-72-0 Daidzein CAS486-66-8 photo picture image Although hip fracture rates are generally lower among Asian populations consuming soy foods than among Western populations, it is not yet clear whether increasing soy isoflavone consumption in Western populations helps to prevent osteoporosis. The results of short-term clinical trials (6 months or less) assessing the effects of increased soy intake on biochemical markers of bone formation and bone resorption are inconsistent. While some controlled trials in postmenopausal women found that increasing intakes of soy foods, soy protein or soy isoflavones improved markers of bone resorption and formation, others found no improvement. Randomized controlled trials of longer duration are required to determine whether increased soy intake can actually prevent losses in bone mineral density (BMD) or osteoporotic fracture. Two controlled clinical trials found that BMD losses over 6 months were lower in postmenopausal women supplemented with soy protein containing isoflavones than in those supplemented with equal amounts of milk protein, but two longer trials found that BMD loss did not differ between postmenopausal women supplemented with soy protein containing isoflavones and those supplemented with milk protein.

 A 2-year clinical trial found that daily consumption of soy milk containing isoflavones decreased BMD loss in the lumbar spine compared to daily consumption of soymilk without isoflavones, but two others studies found that BMD loss did not differ between postmenopausal women taking soy protein supplements containing isoflavones and those taking soy protein supplements without isoflavones. Loss of bone mineral content at the hip over one year was lower in Taiwanese women who took 80 mg/d of isolated soy isoflavones compared to placebo, but the difference was significant only in those women who were at least 4 years past menopause, had lower body weights or lower calcium intakes. While there is some evidence that isoflavone-rich diets have bone-sparing effects, it is not known whether increasing soy isoflavone intake appreciably decreases the risk of osteoporosis or osteoporotic fracture.

 Assessment of soy phytoestrogens' effects on bone turnover indicators in menopausal women with osteopenia in Iran: a before and after clinical trial.:

 Background: Osteoporosis is the gradual declining in bone mass with age, leading to increased bone fragility and fractures. Fractures in hip and spine are known to be the most important complication of the disease which leads in the annual mortality rate of 20% and serious morbidity rate of 50%. Menopause is one of the most common risk factors of osteoporosis. After menopause, sex hormone deficiency is associated with increased remodeling rate and negative bone balance, leading to accelerated bone loss and micro-architectural defects, resulting into increased bone fragility. Compounds with estrogen-like biological activity similar to "Isoflavones" present in plants especially soy, may reduce bone loss in postmenopausal women as they are similar in structure to estrogens. This research, therefore, was carried out to study the effects of Iranian soy protein on biochemical indicators of bone metabolism in osteopenic menopausal women.

 Materials and Methods: This clinical trial of before-after type was carried out on 15 women 45-64 years of age. Subjects were given 35 g soy protein per day for 12 weeks. Blood and urine sampling, anthropometric measurement and 48-h-dietary recalls were carried out at zero, 6 and 12 weeks. Food consumption data were analyzed using Food Proccessor Software. For the study of bone metabolism indicators and changes in anthropometric data as well as dietary intake, and repeated analyses were employed.

 Results: Comparison of weight, BMI, physical activity, energy intake and other intervening nutrients did not reveal any significant changes during different stages of the study. Soy protein consumption resulted in a significant reduction in the urinary deoxypyridinoline and increasing of total alkaline phosphatase (p less than 0.05), although the alterations in osteocalcin, c-telopeptide, IGFBP3 and type I collagen telopeptide were not significant.

 Conclusion: In view of beneficial effect of soy protein on bone metabolism indicators, inclusion of this relatively inexpensive food in the daily diet of menopausal women, will probably delay bone resorption, thereby preventing osteoporosis.

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citations1.The Secret of Soy,What is Soy Isoflavones?Function of Natural Genistein?Soy Bean Extract.

last edit date:6th,May.2009.