It is amazing how many people are scared to smile when they are happy, because they are concerned that people will look at their teeth and notice they aren't white. This is a really revealing fact – smiling is one of the most natural things to do in reaction to something positive happening. It is largely instinctive, and the decision to override your instincts means that you have a very clear concern.
This is one of the major selling points for teeth whitening. If you are scared to smile broadly, then you have to constantly be on your guard. Praise from your boss at work, a compliment from someone you are attracted to, an impromptu photograph – they are all situations that demand a smile, and not smiling in the situation will draw more attention than anything else. If you aren't prepared to smile in this situation then it is clear that you are more concerned about the state of your teeth than you are happy about the situation itself.
A smile is a powerful thing. Smiling at someone can be massively important – showing them that you are interested in them, giving them support for something good that they have done, encouraging them in a difficult situation. Having your smile taken away is a troubling thing. In this respect, it is important to do something about it. Teeth whitening is an investment in yourself, as it allows you to be yourself more. That is something worth any price you can pay.