I didn't know that I couldn't have cucumbers or yoghurt for that matter until I tried the diet. cucumbers are hard to digest for O's. If I have cucumbers, I'll most likely burp a lot, get gas or something in that line. I used to eat a lot of yoghurt but never knew that I couldn't have it (and yet why was I sick?) but now I'll eat a teaspoon of yoghurt and as geana333 said, I'll pay for it. You feel so much better, It's hard, especially at first, but worth it.