Does kombucha or other "acidic" foods like sauerkraut and yogurt harm teeth?
W.D. Miller the founder of the acid / bacterial theory of tooth decay said that a strong tooth resists acid indefinitely, but that a week tooth succumbs to acid rather quickly.
So if your teeth are strong, the no, neither sauerkraut, nor kombucha, nor yogurt, nor any other reasonably acidic food like a lemon will cause tooth decay.
But if your teeth are not strong, it is another story completely. Not strong teeth will succumb to acid rather quickly. In which case kombucha at least will contribute to cavities. I am not too convinced on sauerkraut, but I would definitely eat it with other foods so that the acids in the mouth are quickly neutralized.
If someone is highly susceptible to cavities, or has a toothache, then definitely use those foods with care, and rinse the mouth immediately after consumption. Many probiotic foods help our digestive system, by making our digestion more acidic. So we want these foods in our diet. I find kombucha, even home made, to be too sweet. I suggest avoiding kombucha in individuals who have active tooth decay. When tooth decay is halted, then moderate amounts of kombucha is yummy.
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