Is the cross-contact from a shared toaster really something to worry about? Before now, there hasn’t been a lot of research on the true impacts of different potential cross-contact scenarios such as sharing a toaster with regular gluten-containing bread when you have celiac disease. A lot of recommendations like having a separate toaster are based on assumptions that gluten will be transferred but minimal to no research has been done to prove it. That changed this September 2019, when a new preliminary study came out on different gluten cross-contact scenarios.
What is cross-contact?
For those of you who may not be familiar, cross-contact is a term used to describe when an allergen comes into contact with a food that doesn’t contain that allergen.
An example of cross-contact might be non-gluten-free bread touching gluten-free bread. A lot of people have varying opinions on what level of strictness someone with celiac should take to avoid cross-contact.
Some current generally accepted recommendations:
- Use a separate toaster/convection oven
- Use separate dish cleaning utensils (rags, sponges, brushes etc.) for gluten-free cookware
- Use separate knives and cutting boards for gluten and non-gluten-free foods
- Try to store gluten-free foods separately from gluten-containing food (or above it instead of below it)
- Wash the handles of your cabinets and fridge on occasion
- Use separate griddles, fryers, waffle irons, and other similar appliances
- Use separate condiment containers for gluten-free bread (don’t share butter)
The study “Preparation of Gluten-Free Foods Alongside Gluten-Containing Food May Not Always Be as Risky for Celiac Patients as Diet Guides Suggest” to be published in the Gastroenterology journal, tested three different cross-contact scenarios to see how much gluten was transferred in each instance.
The scenarios in the study included:
- Toasting gluten-free bread in a shared toaster
- Cutting a regular cupcake with a knife, washing the knife, and then using to cut a gluten-free cupcake
- Boiling regular pasta in water, and then boiling gluten-free pasta in the same water
You can find the results in the study but in summary, the only transfer of gluten that was above unsafe levels (determined to be >20ppm) was the cooking of gluten-free pasta in water that has previously boiled regular pasta.
I think it’s important to note however, that some people with celiac react to as little as 5ppm of gluten in their food. So while this research might open up doors for a lot of people with celiac, again, just because some people with celiac can eat something safely, other’s might not be able to.
So what does this mean for people with celiac disease avoiding cross-contact?
This is a preliminary study, which means it’s an initial exploration/review/evaluation of cross-contact situations as they relate to celiac disease. At the end of this specific study, it is cited that “[f]uture larger studies in home and commercial cooking environments should address a wider range of scenarios, cooking surfaces, and types of food. Such studies are needed to inform evidence-based recommendations for best practices for GF food preparation that balance the risk of gluten exposure with harm from anxiety and hypervigilance.”
Essentially, we still need more research on the safety of certain cross-contact situations for those with celiac. Over-restriction and anxiety around cross-contact and food situations are a big problem impacting the quality of life in people with celiac. I’m excited to see more definitive research come out that might potentially open up a known safer world. For now, working with a dietitian specializing in celiac can be a great resource for you if you’re confused on the level of gluten avoidance you should be taking to manage your celiac.
Does hearing this make you uncomfortable? Does it concern you?
It made me uncomfortable to hear too. The lifestyle I’ve mastered and learned to live like the back of my hand could be changing. I might be able to safely eat toast from a shared toaster? WHAT!? If the research continues to trend in supporting these findings, I definitely will need to work hard on challenging my comfort levels and figuring out what is best for me. If you find yourself in the same boat, working with a dietitian can help you do the same.
Like I mentioned earlier in this post, people living a gluten-free lifestyle related to celiac are prone to unnecessarily restricting. I was guilty of this myself in my earlier days of diagnosis. If you’re feeling uncomfortable with these findings too, I’d suggest you try to understand why.
Why does this make you uncomfortable? Why are you uneasy about this possible change?
Again, this is just a preliminary study. Meaning this isn’t definitive, this is just the start of cross-contact research. Which also, can I just say is so exciting! There is finally more research coming out on gluten and cross-contact – yay!
Weisbrod VM, Silvester JA, Raber C, McMahon J, Coburn SS, Kerzner B, Preparation of Gluten-Free Foods Alongside Gluten-Containing Food May Not Always Be as Risky for Celiac Patients as Diet Guides Suggest, Gastroenterology (2019), doi: https://doi.org/10.1053/ j.gastro.2019.09.007.