How old do you have to be for teeth whitening?

I'm 14 and I am about to have enough money to get my teeth whitened, I live in the UK and was wondering how old do you have to be, like is there a legal age, like cosmetic surgery? When I was younger I didn't brush my teeth properly because I was lazy, and now I drink too much coffee, so I kind of want to get them done as they look all yellow, let me know!
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It is not really rec commended that it is done at a young age likes yours as your teeth are still developing and not mature as is the rest of your body at 14. But talk to your dentist and se he will refer you to a hygienist for some really deep cleaning to get them all back up to scratch. He will also be able to tell you whether your teeth will be able to be whitened later on when you are an adult. Some teeth are a colour that will never whitened. So save your money until later on, put it somewhere to grow instead.
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