I drink a lot of coffee and tea, so I wanted to do something about the yellowing of my teeth, so I bought a commercially available toothpaste that looked good. I usually use toothpaste that costs around 300 yen, but this one is three times that price... and the amount is small. So I use a little less. I've been using it for about a month. I use it after every meal, and the yellowing has disappeared and my teeth are white again. I was surprised at how effective it was, as the canines, where I hadn't brushed properly, are bright yellow. If you're concerned about stains from beverages without resorting to a clumsy home whitening method, this product is available at drugstores and supermarkets, so it's worth trying. I've been drinking coffee and tea a little more frequently, and I've noticed that stains are less likely to stick to my teeth. I'm interested in other products, so I won't be buying it again for a while, but I can recommend it.