Some drinks (and other foods) are now made with artificial sweeteners, which do not cause decay. However, as yet there are no artificial acids. There are different types of acid, and although they may all taste sour they do not all have the same aggressive action on calcium based compounds (enamel and dentine etc.).
The commonly used acids in foods and drinks include the following:
The acid that produces the most tooth damage is phosphoric – found in most (if not all) colas. Coke, Pepsi etc. ‘Diet’ or otherwise. After drinking, teeth feel ‘rough’ – this is the etched feeling of loss of tooth surface.
Dentists are now seeing a most alarming increase in the amount of tooth destruction by erosion – which is when the teeth literally dissolve in the acid, especially in the child/youth and young adult group. Possibly this is due to an increase in the availability of this type of drink at schools, sports centres and burger restaurants.
Why phosphoric acid is used is not clear; most recipes are still secret. Due to the acidity, micro organisms such as fungi and bacteria will not be able to grow; the acid thus also acts as a preservative. Acid is also considered a pleasant and refreshing taste.
Other acids may cause the same sensation; however, the widespread use of phosphoric acid is probably due to the fact that when the drink was developed (in the 19th century) phosphoric acid was cheap and easy to obtain.