I started using hydrogen peroxide a couple of years ago as an experiment to whiten my teeth, which it did. I bought regular 3% pharmaceutical solution of hydrogen peroxide from Walgreens (hydrogen peroxide diluted to only 3% strength in 97% water). I followed the directions on the bottle and mixed the solution half and half with water (so the solution was now only 1.5% strength), and swished with it once or twice a day for 30 seconds or so. My friends started mentioning my whiter teeth after a couple of weeks. That was a couple of years ago, but more recently I had a friend to whom I suggested the same thing. He tried it, and actually didn't dilute the hydrogen peroxide any further, but just swished with the 3% dilution from the bottle. After a few weeks he told me that he was really happy because his gums had stopped bleeding when he brushed his teeth. He said his gums had been bleeding a lot every time he brushed for a number of y...