[jack9]

If you stick to fountain sodas, it won't wreck your teeth for decades. The acid in the can (and 2liters, small bottles, etc) is very hard on them.

[stryan]

Is there a study about that? I'd love to see more info on difference in health effects between fountain soda vs bottled/canned.

[Jiocus]

I think this is a misconception. It's not about the fountain vs canned or bottle soda.

Carbon dioxide lowers the pH of a drink to 4.5, which is acidic. The acid pH level erodes teeth and one shouldn't brush their teeth too soon after drinking soda because the enamel can be damaged. (Edit: acid on your teeth is always bad, brushing or not.)

Getting a soft drink from a fountain often means getting a straw for your cup as well. Using a straw to drink does help somewhat to bypass the soda from making contact with the teeth in the first place.

Use a straw, save a tooth.