I'm in Tokyo right now and although it is difficult not knowing Japanese, it's not a huge hurdle. I think if you have dietary restrictions it might be harder, but I've found just smiling and guessing at a menu has ended me up with some amazing meals!

Today I was in a noodle shop where I ordered through a vending machine and was delighted with what I ended up with. I saw that everyone else had a glass of water, but I didn't see where it had come from. I was looking around and started stressing out about how I was going to have to ask for it. Another customer must have noticed my distress and got up, got me a glass of water and came over and handed it to me and said "water" and bowed. It was incredibly nice.

The thing I love about Japan is that people are very genuine in their offers to help. In many countries you have to suspect peoples motives when they offer to bring you somewhere or help you find something. At the very least, many of them ask for money after they have helped you. Not so in Japan. Even though people here are often insecure about using what English they do know (I feel the same way about Japanese), their desire to help is very real.