Understanding Gluten: What it is and where to find it


Everywhere you look these days someone is talking about gluten. Since it seems to be on everyone’s mind and there is clearly some misunderstanding about what it is, how it impacts us and who should care, let’s talk about all of those things.

This is part 1…

What is gluten?

First things first, gluten is a protein found in grains. Remember, almost all foods are made of a mixture of macronutrients. So even though whole grains are mostly carbohydrate, they do have protein, fat, fiber, vitamins and minerals in them.

Now, the whole notion of “gluten” can be a bit confusing as there seem to be two different uses of the word. The first is a generic term used to describe a family of “sticky” proteins in cereal grains. Under this term there is gluten in many grains, including corn and rice. (No doubt you’ve heard of glutinous rice?)

However, there is one particular member of the gluten family that is said to be toxic to humans and this is the one most often referenced when someone uses the word “gluten”. This gluten is made of two protein fractions (i.e., short chains of amino acids) called glutenin and gliadin.

Where is gluten found?

Gluten is in all varieties of wheat, rye, barley and any hybrids of those grains. Wheat varieties include bulgur, durum, einkorn, emmer, farro, graham, kamut, matzo, seitan, spelt, semolina, triticale and whole wheat.

Gluten is also in any product made with these grains including beer, bread, breaded foods (including tempura), breadcrumbs, cakes, cereal, cookies, couscous, crackers, croutons, farina, malt, malt vinegar, muffins, orzo, pastas, pastries, pizza crust, soy sauce, teriyaki sauce, tabbouleh, tortillas, wheat bran and wheat germ.

As well, gluten is found in foods that you’d never expect. Many foods like salad dressings, non-dairy creamer, chocolate milk, processed cheese, seasoned rice mixes, gravies, ice-cream, cold cuts, sausage, veggie burgers, meatballs, canned baked beans, mayonnaise, ketchup and bouillon cubes contain gluten as a binder or thickener.

Some processed foods also contain gluten to keep the foods separated during processing and storage before you consume them. I was shocked when I found out that you can’t trust French fries to be gluten free unless they are freshly made onsite, because a gluten containing food starch is often used to keep the French fries separated during the freezing and frying process.  Other foods like this include roasted nuts and trail mix.

And, finally, foods can be contaminated with gluten in the preparation process. For example, let’s say a restaurant serves fried chicken (for which the batter contains gluten) and house-made French fries. Even if they make the French fries fresh and don’t put any flour on them, the French fries will still contain gluten unless they are fried in a separate frier from the fried chicken.

To avoid gluten, you must look for the following words in the ingredient list, in addition to phrases that actually contain the words wheat, rye or barley:

Amino peptide complex Avena sativa Caramel color (frequently made from barley)
Cyclodextrin Dextrin Fermented grain extract
Hordeum distichon Hordeum vulgare Hydrolysate
Hydrolyzed malt extract Hydrolyzed plant protein Hydrolyzed vegetable protein (HVP)
Malt Malt flavoring Maltodextrin
Modified food starch Modified starch Natural flavoring
Phytophingosine extract Secale cereale Soy protein
Soy sauce Triticum aestivum Triticum vlugare
Vegetable protein Yeast extract

Note: Oats do not contain gluten in their natural form. However, most oats are processed in facilities that also process gluten containing grains, where they become contaminated with gluten containing dust. That being said, per the FDA’s rules a company can label a product gluten-free if it contains less than 20 parts per million of gluten. So oats (or any other food for that matter) may be labeled gluten free even if there is a very small amount of gluten contained on or in it.

What about gluten in non-food products?

Some medications, vitamins and supplements contain gluten as an excipient (again a bulking agent). Because these are ingested and, therefore, come in contact with your digestive system, most experts agree that you should try to avoid taking pills or capsules that contain gluten, if you have a sensitivity of any kind.

Some personal care products such as shampoos, lotions and lipstick also contain gluten. However, I have heard conflicting information about whether a person who is sensitive to gluten should avoid them. Some experts say that for people whose immune systems are incredibly sensitive to gluten that gluten in personal care products can be a problem and trigger the immune system. Other experts say that a significant amount of the product would have to enter the body through the mouth or an open skin wound in order to have any impact. Honestly, I don’t know who to believe at this point, so I leave it up to your discretion (with the input of a healthcare provider if necessary) to determine whether or not you believe your personal care products are giving you any symptoms.


Check out part 2 of the series to understand what gluten does in the body and part 3 to understand how those physiological changes can manifest.


— American Diabetes Association. What foods have gluten? In Food and Fitness. Accessed April 30, 2015.
— Federal Drug Administration. ‘Gluten-free’ now means what it says. In Consumer Updates. Accessed April 30, 2015.
— Mayo Clinic. Gluten-free diet. In Patient Care & Health Info. Accessed April 30, 2015.
— Perlmutter D. Grain Brain. New York, NY: Little, Brown and Company; 2013.

Previous Post Next Post