2. Soda This is an obvious one but well worth repeating. Soft drinks are a your teeth’s absolute worst nightmare. There’s nothing soft about the effect of fizzy drinks on your teeth, they damage them hard and they damage them badly. The quantity of sugar is to blame and the fact that, as a liquid, fizzy drinks will reach every nook and cranny in your mouth. If you are going to indulge in a cold coke on a hot day (and we really wouldn’t blame you if you did) the safest bet is to use a straw to minimize the damage to your enamel and to prevent the intense amount of sugar providing a tailor-made breeding ground for bacteria in your mouth.