Is it safe or effective to gargle hydrogen peroxide for the use of whiting your teeth?

I herd that if you mix hydrogen peroxide with water (about 50 50) and gargle like Listerine it will whiten your teeth in about 3 week.
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Brushing your teeth after every meal will prevent your teeth from getting any worse. And of course keeping away from coffee, tea and smoking will help too. ;-) The crest whitening strips work pretty good. I notice a difference the first few times I used it, but the more I used them though the less difference I saw. As far as the whitening tooth paste and mouth washes, they don't seem to do anything at all. What worked the best for me was this mail order stuff from teethwhiten.com, it worked really quickly. They had a free sample offer so you can try it out and see how it works for yourself. Click the link below if your interested in getting the free sample:
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