Why does my teeth (or gums) hurt when I eat a lot of fruit?

I really love the way I feel when I eat mostly fruits. Right now I am into nectarines and am eating about 9 fruits per day and hardly anything else. About a week after eating like this a few of my teeth really hurt near (or maybe below?) the gums when I brush them, and not just mild pain this pain makes me jump!

Does anyone know why this is happening? I've had similar pains when I was drinking a lot of lemon juice throughout the day and wonder if its the acids. However I usually eat just as many granny smith apples per day sometimes for weeks at a time and this pain doesnt occur with them.

Any ideas on how to remedy this? Tweet