If you are just starting out on a restricted diet, and are dealing with serious food intolerance or sensitivity, then cross-contamination ought to be a serious concern for you. Many people you have a gluten, soy, or dairy sensitivity or intolerance will be able to tolerate traces of the problem food. Lactose intolerance is a good example. Most people who are lactose intolerant do not have to be concerned with minute traces of lactose in their food. For many other people, however, even many who have no idea of how strict they need to be, cross-contamination may be making them sick every day. These people may think that they have been misdiagnosed, they may be in denial about the need to make complete and permanent life and diet changes, or they may be lax in research or checking out what they eat and use. In any event, this article will give you all the basics to identify all the areas of your life that may come into contact with a problem food and to learn how to avoid it completely so you can stop being sick and stop living in pain from cross-contamination.
What is cross-contamination?
Cross contamination means that some substance has unintentionally or carelessly come in contact with a food or item that is safe for you, rendering that otherwise safe food unsafe. The most common causes and sources of cross-contamination are kitchens and factory production lines.
Cross-contamination of food
A) By self
Cross-contamination of food often occurs when we essentially poison ourselves in our own kitchens. For me, even the tiniest traces of gluten or casein (A dairy protein) will make me ill. This means that ALL of my condiments are segregated from those that others will use, or else they are labeled. Imagine if someone is making a sandwich with your mayonnaise and the crumbs get in the jar when they repeatedly dip the knife in. This sort of thing will happen all the time. For myself, a crumb is no laughing matter.
Another common self-contamination of food is dishes, cupboards and surfaces. The biggest culprit is wheat flour. Flour gets into everything and can be near invisible. People do not think of it as a poisonous substance or one that will go bad that they need to be super careful about cleaning up. Kitchens can be like a war zone to someone who is gluten intolerant.
B) By others
The first and most obvious way people face cross-contamination by others is when food is prepared in another person’s kitchen. This includes the kitchen of friends, as well as the kitchens of restaurants.
The next most common source of cross-contamination by others is factor production equipment. Even if the ingredients of the food you are eating do not contain the food or item that you are intolerant to, the other products that the factory produces may contain ingredients that are harmful to you. A great example of this is chocolate. If you are dairy intolerant like me, obviously milk chocolate is off the list. What about dark chocolate, though? Some doesn’t have any dairy at all in it. Surely it is safe to eat, right.
The answer to the above question is unfortunately no. Dark chocolate is almost never safe to eat if you are dairy intolerant. The good news is that most will label their wrapper or package ingredients section with bold type indicating that it may contain traces of dairy. Reputable manufacturers will do this now. They will do this even if they are confident in their factory cleaning and sanitizing practices. They add this info as a legal disclaimer as much as sound advice for the food intolerant peruser.
Unfortunately, there is no sure-fire and pain-free way to determine if that product would be safe for you to eat. There are some tips you can use to help you make an informed decision about whether you are going to eat it anyways. Let me add that you should rarely be eating it. It is never worth it. That was the biggest realization that helped me get pain free. But that sentiment should be in the cheating section, shouldn’t it?
Talk to the company; ask them what their cleaning practices are. Ask them if they stand behind it and if the warning on the label is for legal reasons or if it is a major concern. Next, you want to look on the internet and ask the staff at specialty stores, like vegan shops (for dairy-free products, at least). You will find some items where the company will tell you they use excellent and complete cleaning practices between different types of product batches. Better still, some will tell you that the equipment does is not used for anything that you are intolerant to, but they keep those ingredients in the factory, albeit with safe handling practices. That last one is the safest bet, for sure. I risk it sometimes. The last one is the only category that has not yet made me sick.
Preventing Cross-contamination of food
Let me just reiterate, in case there was any doubt. This article is about what I feel is a huge area of pain-free living for those suffering from a food intolerance. That means that when we are talking about cross-contamination of our otherwise safe foods, and trace amounts of exposure, we are also implying (and now I am expressly underlining) that we never cheat. Cheating causes pain. Rolling the dice causes pain. They are the things that can damage you internally (especially with gluten intolerance, if you are celiac). Make a choice to be pain-free if you really want to live well. It is one or the other. Then here are some guidelines:
- Clean every dish or cutlery before you use it if you are a guest
- Clean your entire kitchen VERY well and I recommend NOT keeping any of the items you are intolerant to in it unless they are in sealed packaging (especially flour).
- Read EVERY label for the rest of your life, starting from this moment forward before you use a product.
- Talk to the restaurant server, have them talk to the chef or cook. Look right into their eyes and make sure they know what the words you are saying mean. If you are not sure, so not eat there.
- Have a snack on you just in case there is nothing you can verify as being safe at a restaurant. You do not have to be embarrassed. If you are in a group, the others will be ordering. Even if a server challenges you (this has never happened to me) you can explain that you have a severe food intolerance and will become severely ill.
- Do not eat a food item that you are not sure about. If you do not know what the words on the label ingredients are, do not buy it or eat it. Make a note and then research it when you get home (or on your smartphone right at the store!).
- Clean, clean, clean
- Be careful of your social behaviour. Don’t clink your wine glass against the beer stein of your toasted friends when toasting to everyone’s health. One little drunken slosh is all it takes.
Preventing Cross-contamination by Non-food Stuff
This is sometimes a surprise for people. This one may also be a gray area, too. Some people who are severely gluten intolerant, and cannot handle any traces of gluten in their foods, are seemingly okay with a shampoo that contains wheat grass or barley extract, or wheat germ, etc. Obviously, that would also mean they are not getting it in their mouths, too. In other words, the set of rules you have for food may or may not apply to every household item and toiletry that you use. My rule in these cases is that it is better safe than sorry.
Other items are more clearly offending our food-based set of rules. If the person you are presently kissing is using a lip balm or a lip stick (or other makeup product on their face where your lips may end up) do you know what it is, and if it contains gluten? These are the sorts of things you want to train yourself to think about all the time. Eventually you should find that you very very rarely end up with the “mystery gluten” or other food intolerance symptoms where you have no clue about the cause. I know how frustrating that can be and how helpless it can make you feel. I want to help you eliminate that feeling of helplessness and give you back control over your health.
In future sections or articles, I will delve more deeply into specific food intolerances like gluten intolerance and dairy intolerance. I will examine the specifics risk factors, science, and pitfalls for each. Stay tuned and let me know if you have questions or comments! Thanks for reading this pillar article on cross-contamination or food, I know it was longer than my typical article, but I hope you found it useful.

