Iodine/Walnut hulls and teeth whitening?

I just wrote a really long post about this and lost it, so to keep it short, anyone got any experience with Iodine as a teeth whitener??

In India and the Middle East we use fresh Walnut Hulls for instant and dazzling teeth whitening. Just by rubbing the mushy inside of the fresh hull on your teeth, you will see instant and dazzling results. Anyone else tried this??

I am wondering if this effect is related to the very high Iodine content of the hulls, which even taste and smell quite like Lugol's. If you let the mushy inside of the hull touch your skin it will stain it, just like Lugol's will!! Yet it dramatically whitens the teeth instantly!

Any opinions or experiences regarding this?? :)

Peace