does citric acid whiten teeth?!

No it won't. It will wear off enamel and actually make your dentin show through more which makes the teeth appear more yellow. Products that whiten teeth break up larger particles in the enamel to smaller ones that show less color. Citric acid just erodes the enamel. Bad idea!

I'm a dentist

It is done by using lemon juice or lemon peels. It will work; however, it is extremely harmful because it ruins the calcium in your teeth and damages the enamel, causing decay.

http://www.bestteethwhiteningoptions.com…

It's ACID. That's a great way to wear down your enamel and weaken your teeth...