Coeliac

[Notters]

Sushi is also a good option.

 

[Garry Nelson's Left Foot]

I have IBS which (for me, at least) incorporates an intolerance of gluten. I've found that Singaporean and Cantonese restaurants are generally good for avoiding gluten. Thai and Vietnamese should also be o.k as they use rice noodles a lot more than they do wheat ones. As Notters says Sushi is also a good option, which would be perfect for me living in Japan except I can't stand fish...