The following post on wheat and barley grass is printed here with permission.

Updated: April 5, 2018

The information below from the FDA about wheat and barley grass originally provided to me in 2010 remains accurate. The gluten-free labeling rule was finalized in 2013. 

In a response to a consumer email inquiry regarding the use of a “gluten-free” (GF) labeling claim for a product made with ingredients like wheat grass and barley grass, Rhonda Kane, MS, RD, a Consumer Safety Officer with the Food and Drug Administration (FDA), gave the following response, explaining aspects of the GF food labeling requirements FDA proposed in 2007; however, FDA has not yet issued a final rule to establish a regulatory definition of GF:

“FDA proposed specific criteria that must be met by any foods bearing a GF labeling claim.  (See page 2817 of the proposal for details.)  Among those criteria are that the food cannot be made with the grains wheat, rye, barely, or crossbred hybrids of these grains (referred to as “prohibited grains”), and that the food cannot contain 20 parts per million (ppm) or more gluten.  We also proposed the term “gluten” to mean the proteins that naturally occur in a prohibited grain and that may cause adverse health effects in persons with celiac disease (e.g., the prolamins and glutelins).  Further, we proposed to define wheat, rye, and barley to include any grains that belong to their same genera (i.e., Triticum, Secale, and Hordeum, respectively).  Consequently, grains like kamut, spelt, durum, etc. that belong to the same genus as Triticum also would be considered to be “wheat” for the purpose of GF labeling.

The young grasses of the plants belonging to genera Triticum, Secale, and Hordeum are different from the grains wheat, rye, and barley these plants produce at maturity.  Therefore, to be consistent with FDA’s proposed requirements, any grass (or grass juice) could be used as an ingredient to make a food labeled GF, provided that the food does not contain 20 ppm or more gluten, regardless of its source, including the presence of gluten due to cross-contact situations.”

Note from Tricia Thompson, MS, RD: Please make sure that any products you consume that contain wheat or barley grass are labeled gluten-free and tested for gluten contamination using the sandwich R5 ELISA. 

Can Products Containing Wheat and Barley Grass be Labeled Gluten Free?