Cross-contamination means that a food or utensil has been exposed to some form of contamination that is indirect or inadvertent. I’m sure most of you have had the experience of choosing a dish at a restaurant that had no obvious wheat/grain ingredients, e.g., no breading, no breadcrumbs, no croutons, no noodles, reassured by waitstaff that the dish was indeed “gluten-free,” only to find yourself sitting on the toilet an hour later forcefully evacuating your bowels, struggling with an attack of anxiety, or sporting a belly looking like you’re about to deliver a full-term infant.
If such wheat/grain re-exposure reactions cannot be blamed on obvious sources, then it’s likely to be due to cross-contamination, i.e., exposure to a small residue of some wheat or grain ingredient from contaminated utensils, cooking surfaces, foods, the hands that prepared them, or even air containing airborne flour. Cross-contamination is not just an issue for wheat/grains, but also for exposure to bacteria and other pathogens, such as when the kid flipping burgers at the fast-food restaurant didn’t wash his/her hands after going to the toilet.
People with celiac disease have to be extremely vigilant about cross-contamination. Exposure to, say, eggs fried in a pan that was incompletely cleaned after making French toast will trigger a reaction that can last for weeks or months: diarrhea, bloating, joint pain and swelling, skin rashes, emotional effects. Or slicing mushrooms on a cutting board that was previously used to cut bread will definitely provoke a reaction. It is not just an inconvenience but can have real serious consequences. Repeated exposures in people with celiac disease over time actually exert carcinogenic effects. Eating in restaurants or in social situations can be especially tricky, so hazardous that many people with celiac disease give up trying and simply avoid. The situation is improving, as more restaurants, chefs, and waitstaff are coming to appreciate that segregated work surfaces, cooking surfaces, food, utensils, and even airflow are required to declare a food genuinely and safely “gluten-free,” but they still remain in the minority.
But how much is cross-contamination an issue for those of us without celiac disease? It depends. It depends on factors that include:
- Sensitivity to the immune-activating effects of the gliadin protein and gliadin-derived opioid peptides
- Sensitivity to the brain/emotional effects of gliadin-derived opioid peptides
- Sensitivity to the gastrointestinal toxicity of wheat germ agglutinin
- Sensitivity to allergic effects of the many wheat/grain proteins
- How long you have been wheat/grain-free, as the longer you have been free, the more marked the reactions to re-exposure
(Wheat/grain components such as the amylopectin A and phytates are not issues with cross-contamination as, unlike gliadin that can be toxic in minute quantities, amylopectin A and phytates require greater quantities/volumes to exert their toxic effects.)
For most of us, the cross-contamination that comes through, say, an incompletely cleaned cutting board is not an issue. But, if you find yourself with an adverse reaction after some food, one of your first thoughts should be whether you have become sensitive to the small quantity of wheat/grain residues obtained via cross-contamination. It means having to follow the lead in many of the lessons provided to us by the celiac community: ask about ingredients, ask whether a segregated preparation area was used, try to gauge the level of interest in delivering a genuinely “gluten-free” dish. You may not be as severely sensitive to the components of wheat and grains, but just trying to minimize exposures is absolutely worth working towards.
The power of cross-contamination reactions is, by the way, a vidid reminder of just how toxic wheat and grains are for humans. Can you conceive of any other “food” that, by exposure to the equivalent of a breadcrumb or less, provokes such violent reactions? The people around you unschooled in Wheat Belly concepts or celiac disease will pooh-pooh that such minute exposures could provoke such reactions. But spend a few hours on the toilet after using the same butter knife on your food as that used to butter a slice of bread, or cook your food in an oven used to bake a pie, or find that your knees and hips hurt so much after you used the same dishwashing sponges on your dishes and utensils as that used to clean wheat/grain dishes, and you quickly realize how little most people understand about how toxic these foods can be.