Feeding on what?

For a short recap: we use yoghurt instead of toothpaste when brushing teeth. The yoghurt is a live culture made of various bacteria inherent. Now as you may suspect, as bacteria are living creatures they also need feed. Actually as we are living creatures - human beings - we stuff feed or as we call it food into our mouth. In that food there is ample nutrition for our bacterial buddies. However these food leftovers feed both the good bacteria good guys and the bad. What they like most of it is the sugar. They eat the sugar and produce acid, as simple as that. However an interesting point to observe is that bacteria can eat other bacteria thus 'cleaning up' the overall picture. We attempt to let the good guys bacteria in yoghurt outnumber the inherent bad guys bacteria when using the yoghurt toothpaste replacer method.