Reading labels is a way of life when you have celiac disease. Before eating anything in a package, be sure to read the label carefully. Look for hidden  sources of gluten and for other names, such as food starch, seasoning and hydrolyzed vegetable protein.
Also be on the lookout for precautionary statements. These are statements that indicate gluten may be in the food, due to cross contamination. Examples of precautionary statements include: “May contain gluten” and “Manufactured in a facility that also processes wheat.”
If you are ever uncertain about whether a food product is safe for you, call the manufacturer to confirm. When in doubt, don’t eat it.
In Canada, new regulations have been proposed that would require food manufacturers list priority allergens, including gluten, in plain language on packaging. Ingredients of ingredients that are priority allergens would also have to be listed. For example, manufacturers couldn’t simply list “modified starch” if the source of the starch is wheat.
More on Canada’s Food Allergen Regulations 
Health Canada is also reviewing its gluten-free labeling requirements. Specifically, it is looking at whether a change should be made to the rule that food made with oats cannot be labeled gluten-free. This is in light of the fact that pure, uncontaminated oats are safe for most people with celiac disease and are available in Canada. More  on the proposed changes.
In the United States, the Food Allergen Labeling and Consumer Protection Act, which went into effect in 2006, requires manufacturers to use plain language when listing priority allergens, and to declare all allergens either in the ingredient list, or in a “contains:” statement at the end of the list. This act encompasses wheat, but not other sources of gluten.
Currently in the United States there is no rule governing what can be called “gluten-free” on a food label. A rule was proposed in 2007, but has not been approved.
See: U.S. Proposed Rule  on Gluten-Free Labeling