What Ingredients Can You Not Have If You Are Gluten-Free?

November 23, 2025 •

4 min read

According to the Celiac Disease Foundation, gluten, a protein found in wheat, barley, and rye, is present in many foods and hidden in unexpected ingredients. For those with celiac disease or gluten sensitivity, it is essential to understand what ingredients you can not have if you are gluten-free, as even tiny amounts can cause significant symptoms.

Quick Summary

A guide detailing the primary gluten-containing ingredients to strictly avoid, including common grains and their derivatives, along with the less obvious and hidden sources found in many processed foods, condiments, and flavorings.

Key Points

Core Grains to Avoid: Wheat, barley, rye, and triticale are the primary gluten-containing grains to exclude from your diet.
Watch for Wheat Derivatives: Be aware of various wheat forms like spelt, durum, semolina, and farro, which all contain gluten.
Identify Hidden Sources: Gluten can lurk in processed foods like sauces, condiments (e.g., soy sauce, malt vinegar), and seasoned snacks.
Beware of Malt: Malt flavoring, malt extract, and malt vinegar are derived from barley and are not gluten-free.
Prevent Cross-Contamination: Even tiny amounts of gluten can be harmful, so use separate utensils, cutting boards, and cooking surfaces to avoid contact.
Check for 'Certified Gluten-Free': Always read labels and opt for certified products to ensure they meet strict standards and have a lower risk of contamination.
Scrutinize Added Thickeners: Ingredients like modified food starch, if not specified as wheat-free, can be a hidden source of gluten.

Common Grains and Obvious Sources of Gluten

Gluten is the binding protein found primarily in three grains: wheat, barley, and rye. Avoiding these is the first and most critical step for anyone following a gluten-free diet. The challenge lies in recognizing the many forms and names these grains can take in an ingredients list.

Wheat and Its Derivatives

Wheat is the most prevalent source of gluten in the Western diet. Simply looking for the word "wheat" is not enough. You must also watch for its many different forms:

Spelt: An ancient form of wheat.
Durum: A hard wheat variety often used for pasta.
Semolina: Coarse, purified wheat middlings of durum wheat, primarily used in pasta.
Farina: Milled wheat used in hot breakfast cereals.
Farro: A grain species related to wheat.
Kamut: A type of wheat, also known as Khorasan wheat.
Graham flour: A coarsely ground whole wheat flour.
Wheat bran, wheat germ, and wheat berries: All parts of the wheat grain.
Bulgur: A cracked wheat product.
Couscous: A pasta made from crushed durum wheat semolina.

Barley, Rye, and Triticale

In addition to wheat, barley and rye are fundamental ingredients to avoid. Triticale is a hybrid of wheat and rye, and must also be avoided.

Barley: Found in soups, stews, and many beverages. Malt is made from barley and must be avoided.
Rye: Commonly found in rye bread and certain cereals.
Malt: This term is a major red flag, as it is almost always derived from barley. Be cautious of malt extract, malt flavoring, and malt vinegar.
Brewer's Yeast: A byproduct of the beer-making process, which uses gluten-containing grains.

Hidden Sources of Gluten in Processed Foods

Navigating a gluten-free diet requires diligence beyond just avoiding bread and pasta. Gluten can be a stealthy additive in a surprising number of processed products, used as a thickener, binder, or flavoring agent.

Sauces, Condiments, and Dressings

Soy Sauce and Teriyaki Sauce: Most traditional soy sauces are fermented using wheat. Look for certified gluten-free alternatives or tamari, which is typically wheat-free.
Malt Vinegar: Derived from barley, this vinegar is not gluten-free. Distilled vinegar is generally safe.
Thickeners and Flavorings: Many sauces, gravies, and marinades use wheat flour as a thickener. Look for “modified food starch” or "natural flavors," as they could contain hidden gluten if not specified otherwise.
Salad Dressings: Some salad dressings, especially creamy varieties or those with soy sauce or malt vinegar, can contain gluten.

Meats, Soups, and Snacks

Processed Meats: Sausage, hot dogs, cold cuts, and even imitation seafood can contain gluten-based fillers or binders. Always read the label carefully for added ingredients.
Soups and Broths: Many canned and boxed soups use wheat flour as a thickening agent. Canned broths and bouillon cubes can also contain hidden gluten.
Snack Foods: Flavored chips, pretzels, and granola bars often contain wheat or malt. Even traditionally gluten-free items like corn flakes may contain malt flavoring.
Candy: Certain candies, particularly licorice and malted candies, contain wheat flour or barley malt.

Understanding the Risk of Cross-Contamination

Cross-contamination occurs when a gluten-free food comes into contact with gluten during processing, preparation, or serving. This is a major concern, particularly for individuals with celiac disease, where even a tiny amount of gluten can be harmful.

Common Points of Contamination

Shared Equipment: Toasters, cutting boards, and fryers used for both gluten-containing and gluten-free foods can transfer gluten particles.
Airborne Flour: Wheat flour can remain airborne and settle on surfaces, contaminating gluten-free products.
Bulk Bins: Avoid bulk food bins, as shared scoops can easily lead to contamination.
Shared Condiments: Double-dipping utensils from gluten-containing food into shared jars of spreads or condiments (e.g., butter, peanut butter, jam) can introduce gluten.

Gluten-Containing vs. Gluten-Free Ingredients Comparison

To help simplify shopping and cooking, here is a table comparing common gluten-containing items with safe, naturally gluten-free alternatives.


Ingredient to Avoid (Contains Gluten)	Safe Gluten-Free Alternative
Wheat flour (All-Purpose, Semolina, Spelt)	Gluten-Free Flours (Almond, Coconut, Rice, Corn)
Barley (Malt, Brewer's Yeast)	Naturally GF Grains (Quinoa, Millet, Corn, Rice)
Rye (Rye Bread)	Gluten-Free Bread (Made with GF flours)
Traditional Soy Sauce (Contains Wheat)	Tamari (If made without wheat), Coconut Aminos
Malt Vinegar (Derived from Barley)	Distilled White Vinegar, Apple Cider Vinegar
Conventional Oats (High Risk of Contamination)	Certified Gluten-Free Oats
Wheat-based Pasta (Spaghetti, Noodles)	GF Pastas (Made from Rice, Corn, Lentils)

Conclusion: Navigating a Gluten-Free Lifestyle

Successfully navigating a gluten-free diet means being vigilant not only about major ingredients like wheat, barley, and rye, but also about the hidden sources and risks of cross-contamination. By learning to identify the numerous forms of gluten and reading labels meticulously, you can protect your health while still enjoying a delicious and varied diet. Always opt for certified gluten-free products when possible and remain cautious in shared kitchens or dining out. Empowering yourself with this knowledge is the key to living safely and comfortably with a gluten-free lifestyle. For more information and resources on celiac disease, consider visiting the Celiac Disease Foundation website.

Frequently Asked Questions

The most common grains to avoid are wheat, barley, and rye. Triticale, a hybrid of wheat and rye, also contains gluten and must be excluded.

Traditional soy sauce is fermented with wheat and is not gluten-free. Tamari is a common gluten-free alternative, but always check the label to be sure.

Oats are naturally gluten-free but are often cross-contaminated during growing and processing. You should only consume oats that are specifically labeled 'certified gluten-free' to ensure safety.

Malt is typically made from barley, a gluten-containing grain. It is found in ingredients like malt extract, malt flavoring, and malt vinegar, and must be avoided.

To prevent cross-contamination at home, use separate cutting boards, toasters, and utensils for gluten-free cooking. Be mindful of shared condiments, and wash surfaces thoroughly to remove crumbs.

No. While many food starches are derived from corn or potato, modified food starch can sometimes be wheat-based. Unless the label specifies the source, such as "modified corn starch," it is best to avoid it.

While many restaurants offer gluten-free options, it is crucial to communicate your needs clearly to the staff. Inquire about their preparation methods, and if they use shared surfaces, fryers, or utensils, to minimize the risk of cross-contamination.