Gluten-free is everywhere these days. We have seen a welcomed increase in awareness of celiac disease, a serious autoimmune disease that requires a strictly gluten-free diet and affects roughly 1 in 100 people. Non-celiac gluten intolerances appear to be on the rise, and the popularity of low-carb, ketogenic, grain-free and paleo diets have also increased demand for gluten-free foods. With gluten-free foods popping up in even the most mainstream grocery stores and eateries, eating gluten-free has never been more popular nor easier to do.

However, you are not alone if you have wondered why you are seeing the term “gluten-free” on items that aren’t food!  Seeing your lipstick, shampoo, or skin lotion labeled gluten-free has left many consumers perplexed. After all,  ”gluten” is a protein found in foods – Namely, wheat, barley and rye. Some oats also contain immunoreactive proteins that some bodies react to similarly to wheat gluten, plus they are often contaminated with other gluten-containing grains. When people with celiac disease ingest gluten, the villi of their intestines are dangerously damaged, which may cause everything from diarrhea to weight loss and from nutrient malabsorption to serious neurological issues. This autoimmune disease has serious long-term health effects and can only be treated with a strictly gluten-free diet. Celiac disease is sometimes accompanied by a skin condition called dermatitis herpetiformis. Dermatitis herpetiformis can cause itchy rashes, bumps and blisters. People with eczema and irritable bowel syndrome as well as with some autoimmune diseases (e.g. inflammatory bowel disease, psoriasis, multiple sclerosis and rheumatoid arthritis) may also find that gluten causes flare-ups of their conditions.  But if all of these conditions are triggered by eating these foods, why would it matter if topical skincare products and cosmetics contain gluten?

Take a moment to imagine that you are washing your hair in the shower with a shampoo or conditioner that contains gluten. The water streams down your face, some of it dripping into your mouth. You dry off and apply gluten-containing body lotion, not rinsing off what remains on your hands, which you’ll then use to eat your gluten-free breakfast that may be made of foods that may well be cross-contaminated with small amounts of gluten. Right before leaving the house for work you apply your lipstick or lip balm which you’ll re-apply many more times throughout the day. It contains small amounts of gluten as well. You may also apply more hand cream that will eventually end up in your mouth. These are just a few examples of how gluten can be ingested without eating gluten-containing foods. It’s not hard to imagine how all of these trace amounts can add up to enough unconsciously-ingested gluten to trigger symptoms in the gluten sensitive person!

How much gluten does someone with celiac disease need to ingest in order to have a reaction? A shockingly small amount, it turns out. The ingestion threshold varies greatly from person to person. Research shows, however, that the villi of the intestines can atrophy (causing malabsorption and other symptoms) with the ingestion of as little as 10 milligrams of gluten per day. That is 1/350th of a slice of bread! When you consider the cross-contamination of many of the foods ingested by even people who are careful to stick to gluten-free diets, and add to that the small amounts present in makeup, skincare and body care products, it is surprisingly easy to ingest enough to cause damage and symptoms for those with the highest sensitivity. For some people with celiac disease, and those with wheat allergies, even 10 milligrams is too much.

For those with non-celiac gluten intolerance, irritable bowel syndrome, gluten-sensitive autoimmune diseases like psoriasis or multiple sclerosis, wheat allergies (or allergies to other gluten-containing grains) or eczema that is triggered by gluten ingestion, there is unfortunately no research that shows what a safe threshold is. Therefore, some people may choose to be more careful than others- For example, those who have a history of anaphylaxis or severe skin reactions.

In addition to the accidental ingestion of gluten through products used in the shower or on your lips, topical application on the skin of gluten-containing products can also cause serious reactions for some people with gluten intolerance. The presence of gluten or wheat on the skin can trigger unsightly and uncomfortable flareups of eczema, for example. For people with wheat or oat allergies, it can cause rashes and hives as well as more serious allergic symptoms.

Gluten-containing ingredients to watch out for in cosmetics and hair and skincare products include this non-exhaustive list:

• Wheat and derivatives: Triticum vulgare (wheat) germ extract, germ oil, starch, protein, hydrolyzed wheat protein/PVP crosspolymer, hydrolyzed wheat starch
• Oats and derivatives: Avena sativa (oat) kernel flour, hydrolyzed oat flour
• Rye (Also known as Secale cereale [rye] seed flour)
• Barley flour & barley extract
• Fermented grain extract, hydrolyzed malt extract, phytosphingosine extract,  yeast extract, hydrolyzed vegetable protein, Vitamin E (if derived from wheat germ), S-amino peptide complex, and sodium C8-16 isoalkylsuccinyl.
• Dextrins: Dextrin and maltodextrin (usually gluten-free if made in the United States, but may in some cases contain gluten), dextrin palmitate, cyclodextrin

The core of maintaining one’s health with gluten intolerances and celiac disease is consuming only gluten-free food. Still, learning to recognize gluten-containing ingredients, and identifying skincare and cosmetics companies that make gluten-free products, could play an unexpected role in avoiding symptoms, optimizing health, and maintaining a truly gluten-free lifestyle.

T.Gidseg is a nutrition, health and wellness writer, recipe developer, and mother of 4