Is Your Food Secretly Contaminated? – 10 Sneaky Sources of Gluten that Might Be Making You Sick
- Brainz Magazine
- Mar 27
- 4 min read
Written by April Saunders, Blogger & Registered Dietitian
April Saunders is a Registered Dietitian with a Masters in Public Health. She runs Eats by April – a website dedicated to helping busy moms easily break free from gluten so they can finally feel like themselves again.

Going gluten-free means more than just skipping bread and pasta. It’s a great start, sure to cut out the major offenders of gluten. But when you really want to get to the bottom of your gluten issues, you need to start paying closer attention to hidden sources of gluten in really unexpected places.

If you're not checking labels closely, you might be eating gluten without even knowing it.
10 surprising foods that may contain gluten and how to spot them
1. Soy sauce and other condiments
While soybeans themselves are gluten-free, traditional soy sauce is brewed with wheat, making it a hidden source of gluten.
Other condiments like teriyaki sauce, barbecue sauce, and even ketchup can contain gluten as a thickening agent or hidden ingredient.
What to do: Opt for tamari, a gluten-free soy sauce alternative. For other condiments, read the ingredient list closely or look for certified gluten-free condiments.
2. Oats
Oats are naturally gluten-free, but they’re often contaminated with gluten during processing. Many oat-based products, including granola and oat flour, can have traces of gluten from shared equipment.
What to do: Always buy oats labelled “certified gluten-free” to be sure they haven’t been cross-contaminated.
3. Salad dressings and sauces
Many creamy dressings, gravies, and sauces use flour as a thickener. Even vinaigrettes can contain malt vinegar, which is derived from barley - which is a source of gluten.
What to do: Read ingredient lists carefully and choose brands that are specifically labelled gluten-free, or make your own dressings at home.
4. Processed meat
Deli meats, hot dogs, sausages, and even some bacon brands may contain gluten as a filler or binder. Additionally, cross-contamination can occur if they’re sliced on shared equipment.
What to do: Look for brands that clearly label their products gluten-free and ask your deli if they use separate slicers for gluten-free meats.
5. French fries and fried foods
Potatoes are gluten-free, but when they’re fried in oil that has also been used for breaded foods (like chicken nuggets), cross-contamination can happen. Some french fries also have a gluten-based coating on them, making them an even greater source of gluten.
What to do: Ask restaurants if they use a dedicated fryer for gluten-free items or opt for baked or air-fried options instead.
6. Candy and chocolate
Some chocolates, licorice, and gummy candies contain wheat-based ingredients, especially as binding agents or to add chewiness.
What to do: Check labels for ingredients like wheat starch, barley malt, or modified food starch, and stick to trusted gluten-free brands.
7. Coffee and tea blends
Pure coffee and tea are naturally gluten-free, but flavored varieties may contain gluten-based additives or cross-contamination from processing facilities.
What to do: Stick to plain coffee or tea, and verify flavored varieties with the manufacturer.
8. Flavored chips and seasoned snacks
Potato and corn chips are naturally gluten-free, but added flavorings (like malt vinegar or seasoning blends) may contain gluten.
What to do: Go for certified gluten-free chips and snacks. There are a lot of options out there now, which is great.
9. Soups and broths
Many canned soups and broths use wheat as a thickening agent. Even some “natural” or “healthy” soups may include hidden gluten.
What to do: Choose brands that specify gluten-free on the label, or make homemade broth using gluten-free ingredients.
10. Alcoholic beverages
Beer is an obvious no-go, but even certain liquors, wine coolers, and mixed drinks may contain gluten due to flavor additives or aging processes in barrels sealed with wheat paste.
What to do: Choose gluten-free beers, ciders, or distilled liquors that are confirmed gluten-free. Check the can, packaging, or the manufacturer’s website to know for sure.
Bottom line
Gluten can be sneaky, but with a little awareness and label-reading, you can confidently navigate your gluten-free lifestyle. Always double-check ingredients, opt for certified gluten-free options, and when in doubt, stick to whole, unprocessed foods.
If you’re just getting started with gluten-free eating, head to Eats by April and grab the PDF Checklist of Foods to Avoid so you know what to cut out now and feel better fast.
Read more from April Saunders
April Saunders, Blogger & Registered Dietitian
April Saunders is a Registered Dietitian and runs Eats by April: the place to BE when you first go gluten-free. Fueled by her own experience with years of undiagnosed gluten intolerance, which caused daily stomach cramps, painful bloating, unsightly burping, and brain fog, April finally freed herself of all of it once she went gluten-free. Now, she’s on a mission to help busy moms end their symptoms from gluten intolerance by finally going gluten-free way faster than she did so they can feel like themselves again.