I am a nail tech and esthetician who has a gluten intolerance. My nutritionist has suggested I avoid cosmetics (especially lipstick) and shampoos that contain gluten. I am curious as to how much of what we put on our skin is actually absorbed into our bodies. Can you provide me with more information on this topic?
There is no scientific evidence to support claims that gluten can absorb through the skin. The burden of proof should be on those who make these statements. They should provide credible scientific evidence to back this unlikely claim. What makes gluten unlikely to absorb? Substances with molecular weights (sizes) approaching 500 daltons are considered very poor skin penetrators because they are so large. Any bigger, they can’t possibly absorb into the skin, so they just sit on the surface. Gluten is huge — about 600 daltons — which is pretty monstrous; 15% larger than the theoretical maximum size. Also, gluten is a protein and so is skin. Protein is attracted to proteins, so gluten is likely to bond tightly to skin making it more difficult to penetrate. So it has two things going against it. This is just another example of an unfounded cosmetic myth used to frighten people. The same holds true for lipstick. There is little scientific study that supports the notion that gluten in lipstick is a problem for people with Celiac disease.
In general, very few things can penetrate the skin. There’s only a handful of drugs that can, and they are mixed with "penetration enhancers" to help push them past the skin barrier. Our skin is designed to keep everything out and not much gets past it. I’d be surprised if your skin can absorb even 1/100th of 1% of what’s applied to its surface. It is nowhere near the ridiculously high 60% claim that fear-based advocacy groups often use to frighten people. We could not survive if 60% of what touched our skin absorbed into the blood. It’s a completely unfounded claim. — Doug Schoon is chief scientific advisor for CND