Grains that are safe for coeliac sufferes:
- Cornmeal (as in polenta); also cornflour.
- Buckwheat (good for making pancakes; but check the label because some manufacturers blend it with wheat flour).
- Gram flour (used in Indian cooking, and also for making things like falafel).
You can get gluten-free pasta (corn-based); look in the Free From section of your supermarket.
If you plan to do any baking, look for gluten-free mixes. For example, Dove's Farm do both a g/f bread mix and a g/f self-raising flour. Rice flour is good for making sauces (as is cornflour).
Grains that are NOT suitable for coeliacs:
- Spelt and kamut
- Possibly oats (not sure about that; better check).
You need to be careful. Lots of products contain gluten that you wouldn't expect.
Just looking around my kitchen, I have baking powder, vinegar, ready-made mustard, soy sauce, and a sachet of stir-fry sauce; all these contain gluten. So whatever you buy, be sure to check the allergen listing on the label.
Hope this helps.