I have written a couple of times about products promoted as gluten free. Framed like that, for the vast majority of people they are completely pointless. Unless you know you have a specific problem with gluten there is no reason to seek out gluten free products. But another way of looking at this is to ask whether wheat derivatives are more likely to cause skin reactions than other ingredients. This is not the same question at all. Wheat derivatives are easily substituted by other materials with similar functionality. So if they give rise to more skin reactions than the alternatives maybe it would make sense to take them off the menu. This is the question that the EU’s Scientific Committee on Consumer Safety (SCCS) has just reported on.
Before we go any further, there is a lot of confusion of terms around this. So here is a quick glossary.
Coeliac disease is a specific response to gluten in the diet. It is the result of the body reacting to a particular protein. This provokes an allergic reaction, so it is a very particular kind of allergic reaction. Symptoms vary from person to person but they can include a skin reaction. Nearly all coeliac reactions are caused by eating food containing gluten. But one of the features of allergic reactions is that they can create a sort of chain reaction triggering off problems throughout the body. The way the skin can be affected from an exposure in the gut is a good example. Gluten contact from the skin can also trigger off more general symptoms, but it is pretty rare for it to happen that way round. For the source of the gluten on the skin to be a cosmetic product is rarer still, though not totally unknown.
But coeliac sufferers generally don’t need to worry too much about their cosmetics. The Italian society has even gone out of its way to warn its members that they don’t need to buy special cosmetic products. (Thanks to Angelina Michelotti for the link http://www.celiachia.it/menu/faq.aspx?idcat=14&idfaq=65 )
An allergy to gluten in particular or wheat derivatives in general is a different condition. It is an allergic reaction but it has a different immunological profile and has no direct connection with coeliac disease. Both conditions are rare, but there are people who are unlucky enough to have both.
What is actually going on in an allergy is that the body’s immune system is recognising something as foreign and reacting to it. It doesn’t necessarily recognise the whole thing. Indeed it usually doesn’t. This is something that is particularly important when you are talking about proteins. Proteins are chains made up of amino acids. There are about 20 different amino acids, so if you gave each amino acid a different letter from the alphabet you could describe a protein by a string of letters. The allergic reaction would be to a particular sequence of letters.
So when we ask the question about whether hydrolysed wheat protein is more of a problem than others, what we really mean is are there sequences of amino acids that are particularly prone to provoke a reaction. There is no theory available to predict this. It is just a matter of assessing the available evidence. So this is what the SCCS have done. They had a pretty tough job, because there is all sorts of data to consider but none of it was generated with the particular question they had to answer in mind. Their conclusion was that there was not really a problem, but that it would be a good idea to stick to the shorter protein chains. This is logical when you consider that the strings of amino acids would be that much shorter.
Another point the SCCS picked up on is that soaps and surfactants seem to enhance the chances of a reaction. This again is pretty logical given that they are likely to disrupt the skin’s barrier function. The problem that seems to have triggered the SCCS investigation was a supposed epidemic of sensitisation in Japan where a long chain hydrolysed wheat protein was released in a soap. That was pretty much the worse case.
So all in all the conclusion has to be hydrolysed wheat protein is no risk to the people with normal skin. It would probably do no harm to people with a specific problem with wheat proteins either, but given that it is something you can live without there is no really strong reason to take the risk. You can tell whether it is being used easily enough simply by consulting the ingredient list.