1. Coconut oil: I have already mentioned this before in my post about some uses of coconut oil, but I will still say it again. Coconut oil works by sucking up the impurities and bad bacteria from your mouth ( swish your mouth with coconut oil every night for 20 minutes before you go to bed). Don't forget to spit the coconut oil out at the right time! If you go over 20 minutes, the impurities will be reabsorbed, but on the other hand, if you swish for less than 20 minutes not all the impurities will be taken out, so as you can see it is VERY important to get the timing just right. By sucking out the impurities and bad bacteria, you also remove some surface stains therefore brightening and whitening your teeth.
2. Baking soda: Baking soda works by removing serface stains (similar to coconut oil). Have a bowl
of baking soda in the bathroom and every night before you brush your teeth with toothpaste, brush
them with baking soda for no longer than 2 minutes. (Baking soda is abrasive, so it could cause damage to your teeth if used any longer than that).
3. Lemon juice: lemon juice will whiten your teeth, but it does that by eating away at your enamel (the top layer of your teeth) so lemon juice actually has to damage your teeth in order to whiten them. I don't recommend this method as it could lead to sore and damaged teeth.
Whitening teeth is a tricky business: you want to take off the surface stains to show off your
beautifully whitened teeth, but if your trying to do it naturally, then you want to do it without bleaching or causing damage. Some teeth that are not white are caused simply because your enamel is
thicker, but for some, it's caused by surface stains.
Please know that these methods might not work for everyone.