5 Most Common Questions About Cross-Contact, Answered

Just how careful do you need to be when it comes to food preparation?

When I was first diagnosed with celiac disease and told by my GI doctor that I would need to go gluten-free, I thought the change to my eating routine would be pretty simple.

After all, I already ate a lot of naturally gluten-free foods, like salmon, chicken, rice, quinoa, and vegetables. Plus, having worked as a health writer for many years, I had sampled quite a few gluten-free packaged foods—so I was familiar with a few of the popular brands out there already.

However, about a week after I got my diagnosis, I met virtually with a dietitian who schooled me on something called “cross-contact.” I had never heard this term before and didn’t realize what a wrinkle it would throw into my new gluten-free lifestyle.

Not only would I need to adhere to being gluten-free for life—but I would also have to make sure that all of my meals were prepared in such a way that nothing came into contact with gluten during the cooking process.

That’s because ingesting even a small amount of gluten can cause intestinal damage in someone with celiac disease—even if they experience little or no symptoms. (For reference, most experts say people with celiac disease should consume no more than 10 milligrams of gluten daily, which is basically a few itty-bitty crumbs.)

Once I educated myself more about cross-contact, I decided that making my entire kitchen gluten-free would be the best solution to avoid any unnecessary stress. I tossed cookware that can hold onto gluten even after being cleaned (like wooden spoons) and stocked up on gluten-free breads, pastas, and other packaged items.

For about the first year of my diagnosis, I ate almost all of my meals at home because it was very early on in the pandemic and it wasn’t possible to dine out at restaurants. So, I didn’t have to worry much about cross-contact since I was only cooking gluten-free foods. But in 2021, when restaurants started allowing guests again, I had to learn what questions to ask to avoid it.

These questions included things like: Do you boil your gluten-free pasta in the same water as the regular pasta? Do you have a separate fryer for French fries—or are they fried in the same oil as gluten-containing foods? Trust me, I’ve definitely had some waiters stare at me blankly when I ask these questions.

Whether you’re new to the gluten-free life or simply would like a refresher, I tapped a fewc dietitians and nutrition experts to answer the most common questions about cross-contact.

1. What is cross-contact as it pertains to gluten?

“Cross-contact with gluten occurs when gluten-free food comes into contact with gluten-containing food or surfaces, utensils, or equipment that have been used with gluten-containing foods,” explains Danielle Crumble Smith, RDN, LDN, with Top Nutrition Coaching who has celiac disease herself. “This contact can transfer gluten particles to the gluten-free food, making it unsafe for individuals with celiac disease.”

Cross-contact can happen with food allergens, like peanuts too, making a dish unsafe for someone with allergies, adds Catherine Gervacio, RD, nutrition writer for Living.Fit. 

2. What’s the difference between cross-contact and cross-contamination?

A lot of times, you’ll hear people use these two terms interchangeably, but they’re actually not the same thing. Sure, using the term “cross-contamination” when you’re really speaking about “cross-contact” isn’t the end of the world—but I still think it’s important to understand the difference between the two terms and for you to be able to speak accurately about things related to celiac disease so you can avoid any confusion or mishaps.

Now you know that cross-contact occurs when gluten-free food comes into contact with gluten-containing foods or surfaces, utensils, or equipment used to make gluten-containing foods.

But what about cross-contamination? This “involves the transfer of harmful elements, like bacteria, allergens, or other unwanted substances, from one place to another,” says Gervacio. “One example is when after slicing raw chicken on a cutting board, you use the same board to chop vegetables for a salad without washing it. Now, there's a risk of bacteria from the raw chicken contaminating the veggies, which could cause foodborne illness.”

I enjoyed this fried calamari at Senza Gluten by Jemiko, a dedicated gluten-free restaurant in NYC. Since they only serve gluten-free food, there’s no risk of a shared fryer!

3. What are the most common sources of cross-contact in a kitchen?

According to Crumble Smith, some of the most common sources of cross-contact in a kitchen include:

• Shared toasters, where bread crumbs from gluten-containing bread can stick and transfer to gluten-free bread. 

• Pizza ovens are a common source of gluten particle transfer, so try to select restaurants that have a dedicated gluten-free pizza oven. 

• Shared fryers used for both gluten-containing and gluten-free foods. 

• Buffet stations or serving utensils, where spoons or tongs used for gluten-containing dishes can come into contact with gluten-free options. 

• Cutting boards, countertops, and cookware that aren’t thoroughly cleaned after being used with gluten-containing foods. 

• Spreadable condiments, like butter or jam, where a knife used on regular bread might be dipped back into the container.

4. How can you prevent cross-contact if you share a kitchen with someone who eats gluten?

“It can be a challenge to prevent cross-contact when sharing a home with family or roommates who consume gluten,” notes Belinda Whelan, host of The Healthy Celiac podcast. “But with strategies in place, you can set your home up to work for your unique situation.”

According to the experts I chatted with for this piece, some easy things you can do to prevent cross-contact in your home kitchen include:

• Designate specific gluten-free cooking utensils and equipment. Separate toasters (one for gluten-containing bread and one for gluten-free bread) are an absolute must. If possible, you should use separate cutting boards and knives too.

• Always clean shared surfaces thoroughly before preparing gluten-free food.

• Store gluten-free foods in separate, sealed containers to avoid accidental contact.

• Educate your family members or roommates about the importance of preventing cross-contact.

Here I am at Senza Gluten by Jemiko. My first choice is always to dine at a dedicated gluten-free restaurant if I can find one.

5. How can you prevent cross-contact when dining at a restaurant?

“Eating out with celiac disease is possible when you are confident to ask your waitstaff or chef about their food preparation procedures,” says Whelan. And keep in mind: “Just because a menu item says it’s gluten-free doesn’t always mean it’s ‘celiac-safe,’” she adds.

For example, I once went to a restaurant that listed chips and guac on the menu as being gluten-free, but upon asking how the chips were prepared, the waiter told me they were fried in the same oil as gluten-containing foods and were, in fact, not celiac-safe. (Hey, at least he was able to answer my question!)

Per the experts I spoke with, some things you can do to avoid cross-contact at restaurants include:

• Choose dedicated gluten-free restaurants or establishments that have a good reputation for handling gluten-free meals. (I like to use the Find Me Gluten Free and Gluten Dude apps to do this.)

• Inform the server, and if possible, the chef of your celiac disease and the necessity of avoiding cross-contact. (Even though it’s not an allergy, sometimes telling restaurant staff you have a severe gluten allergy works better because it’s easier for people to understand the concept of food allergies.)

• Ask about the restaurant’s kitchen practices when it comes to handling gluten and whether they have dedicated gluten-free prep areas.

• Avoid high-risk items like fried foods from shared fryers or buffets.

• Communication is key, so don’t be afraid to ask specific questions to make sure you won’t accidentally be exposed to gluten.

The bottom line: “Remember, for people with celiac disease, even a tiny amount of gluten can trigger a reaction,” says Crumble Smith. “I have celiac disease and can vouch first-hand the importance of being as careful as you can. Feeling sick isn't worth it.”