5. Whitening Your Teeth 

Sticking to using the inner side of a banana peel to rub your teeth can be a cheap and effective method to sparkle your teeth. As the salicylic acid and citric acid retained in it can remove the surface stains of teeth without wearing down your enamel. It's better than using chemicals which make your teeth uncomfortably sensitive, and it also saves you a lot of money compared to having professional teeth cleaning.