Most people know to avoid bread, pasta and cakes when eating gluten-free. But for anyone with celiac disease - like Glow Besties co-founder Leonie - that knowledge only scratches the surface. Gluten has a way of appearing in the most unexpected places: a dash of soy sauce, a coated vitamin tablet, a favourite lip balm. Living or travelling fully gluten-free means developing a second sense for these hidden sources, and that knowledge takes time and a fair few frustrating label-reading moments to build. This guide brings it all together in one place, so you can navigate your day with confidence rather than anxiety.
Why gluten hides where you do not expect it
Wheat, barley and rye are remarkably versatile ingredients in food manufacturing. They act as thickeners, stabilisers, flavour carriers and binders - which is exactly why they end up in products that have nothing to do with baked goods. Manufacturers are not hiding gluten to catch people out; they are using it because it works well. The challenge is that ingredient lists use dozens of different names for the same protein: modified starch, malt extract, hydrolysed vegetable protein, triticale, semolina, spelt, kamut and durum are all forms or relatives of gluten-containing grains.
Cross-contamination adds another layer of complexity. A product can be made from entirely gluten-free ingredients but processed on shared equipment or in a shared facility with wheat-containing products. For people with celiac disease, even trace amounts matter. That is why looking for certified gluten-free labels - not just reviewing the ingredient list - is so important in higher-risk product categories.
Sauces, soups and dressings
This is where most people are caught off guard. Soy sauce - including the kind served at Japanese restaurants - is traditionally brewed with wheat. Worcestershire sauce, many stocks and bouillon cubes, gravies, oyster sauce and most commercial salad dressings contain gluten either as a thickener or as a flavouring agent. Malt vinegar, which is made from barley, is another frequent offender in condiments and pickles. Even some mustards include wheat flour as a stabiliser.
Practical swaps exist for almost all of these. Tamari is a Japanese soy sauce brewed without wheat (always check the label, as some tamari brands still add a small amount). Coconut aminos are a naturally gluten-free alternative. When eating out, it is worth asking specifically about sauces and marinades, since a dish can be gluten-free in its main ingredients while the sauce brings in gluten.
- Traditional soy sauce - swap for certified gluten-free tamari or coconut aminos
- Stock cubes and powders - look for certified gluten-free versions or make your own
- Malt vinegar - swap for apple cider vinegar or white wine vinegar
- Commercial salad dressings - check every label; oil, vinegar and lemon juice are always safe
- Worcestershire sauce - gluten-free versions are widely available
Processed and "healthy" foods
The wellness aisle is not automatically safe. Many protein bars use wheat as a bulking agent or are produced in facilities where cross-contamination is likely. Flavoured nuts and crisps often have a coating that includes wheat flour or malt. Some breakfast cereals labelled as "natural" or "high-fibre" contain barley or oats that are not certified gluten-free. Oats deserve special attention: they are naturally gluten-free, but almost all commercially grown and processed oats are contaminated with wheat during harvesting or milling. Only oats with a certified gluten-free label are safe for people with celiac disease.
Processed meats - deli cuts, sausages, burgers, meatballs - frequently use breadcrumbs, wheat starch or rusk as a filler and binder. This is true even of products that do not taste or look like they contain any bread. Vegan and plant-based meat alternatives deserve extra caution: seitan is literally wheat gluten, and many meat-free products use it as their primary protein source. Always read the label, even on brands you have bought before, as formulations change.
- Protein bars and energy bars - look for the certified gluten-free symbol
- Flavoured nuts, popcorn and crisps - plain, unseasoned varieties are safest
- Oats - only buy certified gluten-free oats if you have celiac disease
- Sausages, burgers and deli meats - rusk and wheat starch are common fillers
- Seitan and many vegan meat alternatives - contain wheat gluten by definition
Non-food sources (medication, cosmetics, supplements)
This is the category that surprises people most. Some prescription and over-the-counter medications use wheat starch as a filler or binder in the tablet coating. If you are starting a new medication, it is worth asking your pharmacist to check whether the specific formulation contains gluten. In the EU, manufacturers are required to declare wheat-derived ingredients on the patient information leaflet, but the wording can be buried in technical language. Your pharmacist can help you find a gluten-free equivalent if needed.
Cosmetics and personal care products are a lower priority concern for most people, because gluten is only a problem when it is ingested - skin contact alone does not trigger an intestinal response in celiac disease. However, products that are applied near or on the mouth are worth checking. Lip balms, lipsticks and some toothpastes can contain hydrolysed wheat protein, wheat germ oil or similar derivatives. Nutritional supplements, including vitamin capsules and protein powders, may also use wheat-based excipients. Look for the certified gluten-free label, or contact the manufacturer if in doubt.
How to read labels with confidence
In the European Union, the 14 major food allergens - including gluten-containing cereals - must be clearly highlighted on ingredient lists, typically in bold type. This makes scanning labels much faster once you know what to look for. The key terms are: wheat, rye, barley, oats (unless certified gluten-free), spelt, kamut and products derived from these, such as malt, malt extract and malt flavouring. The phrase "may contain traces of wheat" or "produced in a facility that also handles wheat" indicates cross-contamination risk - whether that is acceptable depends on your individual sensitivity level and should be discussed with your doctor or dietitian.
The most reliable shortcut is the certified gluten-free symbol - either the EU legal claim "gluten-free" (meaning less than 20 ppm) or the crossed-grain symbol issued by the Association of European Coeliac Societies (AOECS). "Wheat-free" is not the same as gluten-free, because a product can be wheat-free but still contain rye or barley. Building a small reference list of trusted brands in each product category reduces the daily label-reading load considerably. At Glow Besties Retreats, every single meal and ingredient is vetted to be fully gluten-free - because Leonie has celiac disease, this is non-negotiable rather than an afterthought.
- Look for bold-highlighted allergens in EU ingredient lists
- Seek the certified gluten-free symbol or the crossed-grain (AOECS) symbol
- Note that "wheat-free" does not mean "gluten-free"
- Treat "may contain traces" warnings according to your personal sensitivity
- Build a trusted brand list per category to reduce daily label fatigue
FAQ
Where does gluten hide most often?
Beyond obvious sources like bread and pasta, gluten turns up most often in soy sauce, marinades, stock cubes, salad dressings, malt vinegar, processed meats, flavoured crisps, and oats that are not certified gluten-free. Checking ingredient lists every time you buy a product - even a familiar one, as recipes change - is the safest habit.
Can medication or cosmetics contain gluten?
Yes, both can. Some tablet coatings and capsule fillers use wheat starch as a binding agent. Cosmetics such as lip balms, lipsticks and some face creams may contain wheat-derived ingredients like hydrolysed wheat protein. If a product is applied near the mouth or if you have celiac disease, it is worth checking the ingredient list or asking the manufacturer directly.
Which labels can I actually trust?
In the EU, the label "gluten-free" is legally regulated and means the product contains no more than 20 parts per million (ppm) of gluten. The crossed-grain symbol from the Association of European Coeliac Societies (AOECS) provides additional third-party certification. Labels that only say "wheat-free" do not guarantee a product is free from other gluten-containing grains such as rye or barley, so always look for the specific gluten-free claim.