Isoflavones protective action

Antioxidant action is one of the mechanisms that may contribute to the cardiovascular protective effects of soy and soy isoflavones. Antioxidant properties have been reported for isoflavones both in vitro and in vivo (see Section 7.3.5). 

Although toxicity from isoflavones may arise from their action as alternative substrates for the enzyme thyroid peroxidase and people in southeast Asia would be protected by the dietary inclusion of iodine-rich seaweed products, a recent study has shown that isoflavone supplements do not affect thyroid function in iodine-replete postmenopausal women. Considerations of the safety of soy isoflavones is an area of great interest in relation to their potential benefits to human health and has recently been comprehensively reviewed. ... 

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