Free radicals are continuously formed in our body as normal by-product of metabolism. Sometimes these free radicals are needed to fight against intruders such as bacteria and viruses. But free radicals can do a lot of damage. They react with essential molecules such as DNA, membranes and proteins. These damages can be life threatening.
Isoflavones have the property to neutralize free radicals. Among the isoflavones, genistein has the highest antioxidant activity. Genistein’s ability to act as antioxidant may also explain the anti-carcinogenic effect of this isoflavone.In our body Superoxide Dismutase (SOD) is produced to remove free radicals. Genistein seems to increase the production of this favourable SOD. Isoflavones, through their antioxidant action, also prevent cholesterol from damaging artery walls.
Several studies have evaluated the antioxidant potential of soy. One test showed that men who drank daily 1 liter soy milk were significantly more protected against oxidative damage to DNA than controls consuming cow’s milk or rice milk. Another study showed that the isoflavone genistein enhanced the activities of antioxidant enzymes in the skin and small intestine of mice.
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