If you are a big tea drinker and concerned about staining, the bottom line is to not let your tea leaves steep for longer than recommended and to choose a tea that requires a lower brewing temperature and shorter brewing time.
For instance, black teas tend to have longer and hotter brewing times which may be another reason why those teas can produce increased tooth staining. Also if you are someone who leaves your tea bags in your cup while you enjoy your tea, you might experience more staining.
If you are wondering how much staining this is, let’s say that you meant to brew your tea for 5 minutes and accidentally let your tea steep for 10 minutes, this translates into 30-40% more staining molecules in your cup. (tea steeping infographic via UtilityJournal)