In general, we recommend to only consume products that are labeled gluten-free (this does not apply to things like fresh produce, but any processed foods, as well as naturally gluten-free grains and legumes need to be labeled.) If they are labeled gluten-free they have to adhere to the FDA threshold of less than 20 parts per million (ppm) of gluten, which is considered safe for people with celiac disease.
A study found that about 20% of foods with no gluten ingredients but not labeled gluten-free contained more than 20 ppm gluten, and 10.2% contained more than 100 ppm gluten. In contrast only 1.1% of foods labeled gluten-free contained over 20 ppm gluten, so it is definitely a lot safer to consume foods that are labeled gluten-free (1).
However, I want to note that many sources of oats, even some that are labeled gluten-free, have had cross-contact with gluten. NCA recommends consuming oats that use the "purity protocol" (have been grown, harvested, transported and processed gluten-free), as well as sources of oats that are rigorously tested to contain below 20 ppm gluten. You can read more about our stance on oats here and decide what is right for you. Also, always check with your doctor if it is ok for you to consume oats.
You can read more about labeling here:
- Sharma GM, Pereira M, Williams KM. Gluten detection in foods available in the United States - a market survey. Food Chem. 2015;15(169):120-126
Note: This information is provided by NCA and Katarina Mollo MEd, RDN, LDN, NCA's Director of Education. This information is meant for educational purposes only and is not intended to substitute for personalized medical advice or replace any medical advice provided directly to you by your health care provider. No liability is assumed by the NCA or Katarina Mollo, MEd, RDN, LDN by providing this information.