Ways to naturally whiten your teeth?

I need some good ways to whiten my teeth. I've been using baking soda for about two months and it hasn't helped at all... So if you know any ways besides getting them whiten at a dentist or by whitening strips please tell me. Thanks!
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Baking Soda Using baking soda between once and twice a month in order to whiten teeth is often recommended by dentists. All that you need to do is mix baking soda with water in a small Dixie cup, dip the tip of your toothbrush in the solution and lightly brush your teeth. Keep in mind, however, that you should not do this more than recommended. Also make sure that you do not swallow any of the baking soda when you brush your teeth. Lemon Juice Rinsing your mouth with a 75% lemon juice and 25% salt solution is known to work wonders for whitening teeth. Unfortunately, there are a variety of different reasons why it might not be suitable for you. If you are on a low sodium or low acid diet, chances are that you will not want to try this out, in case you should accidentally swallow some of the solution. Remember that you should not swallow the lemon juice solution. Another reason why it might not be suitable for you is if you have sensitive teeth, as many people tend to claim that it hurts their mouths. If neither of these things are a problem for you and you can handle the awful taste that you may be dealing with, then you should definitely try rinsing with a lemon juice solution. Rinse with Listerine and/or Peroxide One of the best ways to whiten teeth is by using Listerine or peroxide. Both of these products are known to have a whitening effect on teeth. A certain amount of Peroxide can even be found in tooth whitening at-home products, which shows just how effective it can end up being for you. Can't bear the test of Peroxide? That's okay. You can mix a 50% Listerine and a 50% Peroxide solution, which should help you better accept the taste. The best thing about using Listerine and Peroxide is the fact that both of these products will help you keep germs out of your mouth, which ultimately means that your chances of catching a cold will be a lot slimmer. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~… Avoid drinking red wine and coffee because these can stain your teeth quickly. Smoking on the other hand, can turn the color of your teeth to yellow. Drink milk and lots of water instead Eating fruits and vegetables is also beneficial for the teeth. Raw vegetables are not only healthy but can also clean your teeth; so have them for your snack. Strawberries are loaded with Vitamin C which has bleaching elements. You can also use lemon peel to whiten your teeth; just massaged it over the surface of your teeth and rinse thoroughly.
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