Having whiter teeth can brighten your whole appearance, making you look younger and more attractive almost instantly. And whether you have it done professionally at the dentist's office, or use a do-it-yourself kit at home, it's a pretty basic process.

All teeth whiteners do their whitening with peroxide, and they only differ in how the peroxide is delivered and how strong the peroxide concentration is. You'll get a much stronger and more effective treatment at the dentist, but it'll cost a lot more too. And if you have dull teeth you should know that smoking and coffee-drinking aren't the only culprits -- things like blueberries, red wine, and even tomato sauce can cause discoloration. Also, you won't get the effect you want if you have gum disease so don't even bother (unless you're going for a two-tone look).

Whitening your teeth is really just a cleaning process that has surprisingly few side-effects, so if you're looking to give your looks a boost it might be something to consider. Just make sure you don't overdo it and end up with a glow-in-the-dark/Cheshire cat smile!