It's not a problem if you have yellow teeth. Many people struggle with this problem. Although some people were born with teeth that are darker than others, teeth can be stained over time. This is caused by a range of reasons, such as the following: Consuming certain beverages and foods http://bonsaiwaiter5.bravesites.com/entries/general/teeth-whitener-from-yellow-to-white-in-just-a-couple-of-minutes