It's not a problem when you're suffering from yellow teeth. Many people struggle with this problem. Although some people were born with teeth that are more yellow than others, the teeth of others can be stained over time. This is because of a variety of reasons, such as the following: https://historyhub.history.gov/external-link.jspa?url=https://www.getteethwhitener.com/category/faq-01/page/5/