According to new research, adding milk to tea can be as effective as whitening toothpastes when it comes to fighting off stains, and could actually be as good as some bleaching products. According to Dr Ava Chow, of the University of Alberta’s School of Dentistry, the addition of milk to tea – which would normally cause teeth to become stained – could reduce enamel stains and help teeth to stay whiter.
Dr Chow explained that the tannins in tea – water soluble compounds – is what causes the staining, but that the main protein found in milk can bind the tannins to stop stains from developing. The study was initially supposed to be used to introduce undergraduate dental hygiene students to research techniques but Dr Chow was surprised by the results and felt that they were significant enough to warrant publication in the Journal of Dental Hygiene.
Using human teeth that had been extracted, the study involved placing the teeth in a solution of tea on its own or tea with milk, with the results being recorded after twenty-four hours. Dr Chow said that ‘The results we found showed that casein is the component of milk that is responsible for the reduction in tea-induced staining. The magnitude of the colour change observed in our experiments is comparable to the colour change seen by vital bleaching products and more effective than whitening toothpastes.’