Reading gluten-free labels can be confusing. The good news is that in 2013 the US FDA approved legal standards for gluten-free labels. Still, if you want an easy way to determine if a product is truly gluten-free, look for the seals on products that have been certified by an independent organization.
In the 2013 law, the FDA defines a product as gluten-free if it does not contain the following: wheat, rye, barley, or any hybrid of these grains; ingredients such as wheat flour that have not been processed to remove gluten; or any item made up of more than 20 parts per million of gluten.
Your best bet when buying something that comes in a bag, box or can is to look for a gluten-free certification badge. Manufacturers pay for this certification and go through regular inspections and auditing of their facilities
Gluten-Free Certified Labels
Products labeled with this logo are certified gluten-free by the National Foundation for Celiac Awareness and have 10 parts per million or less of gluten.
The Celiac Sprue Association also certifies gluten-free with a threshold of 5 parts per million. Celiac Sprue Association
Products Without Gluten-Free Badges
If the product does not show a certification badge the next step is to look for a gluten-free statement. This is no guarantee but it is one step. I feel comfortable if it states that it is produced in a dedicated gluten-free facility. The gluten-free certification process is very costly so many smaller facilities chose to forego it.
Next read the ingredients. The first place I look in the ingredients is at the end. A 2004 law requires that wheat be clearly stated on the label. Labels may say “contains wheat” or “manufactured in a facility that also processes wheat” or “manufactured on the same equipment that processes wheat.” The latter 2 mean that wheat is not an ingredient but it may have traces. For someone with Celiac Disease or a severe gluten allergy or intolerance these products are not safe.
Here’s where it gets a little more complicated. There are still barley and rye to consider. Rye almost never hides as anything other than rye. But barley does hide under several aliases and there are no current regulations for barley. Malt, malt syrup, and brewers yeast are just a few ingredients to look for. Maltodextrin is ok as long as it is not derived from wheat. Labeling will indicate if that is the case.
For some more specifics on how to shop for grains check out my article on gluten-free grains.