The other day, a friend mentioned how she loved tea but stopped taking it after her dentist asked her if she smoked because of teeth stains. Well yes, tea does stain. It contains tannic acid. You'll have an idea when you see the thin film on the surface of cold tea. Coffee, red wine and fruits such as apples and blueberries also contain this chemical and can stain teeth.

I am a tea drinker and a fruit lover myself and have to admit there are days when my teeth are less than pearly white. However, they never get to the point of looking almost brown. Aside from the dental check-up every six months, that's when I have my teeth cleaned, I gently brush my teeth with baking soda once or twice a month. It takes out the stains and even my dentist says that's why my teeth don't need heavy-duty cleaning.

A word of caution though: don't over-brush your teeth with baking soda with say, thrice a month. You might harm the enamel and risk ruining your teeth.