Our Journey with "May Contain" Warnings: From Avoidance to Confidence

I frequently share on Instagram that we do not avoid products with a precautionary label (“may contain,” “shared facility,” etc.). But it wasn’t always this way.

Here’s our journey all about how we got here, and some resources to help you decide what’s best for your family. Please speak to your allergist about how to handle precautionary warnings.

Preface: Ingredient label vs. precautionary warning

First, it’s important to differentiate the two things you might see on the back of a package.

There’s the ingredient label itself. There are lots of rules around how (in the U.S.) top 9 allergens are required to be disclosed on an ingredient label in plain English. FALCPA and the FASTER Act made it so. So if egg is an intended ingredient, the ingredient label is where it must be displayed. In addition, those bold “contains” statements are voluntary. So if you don’t see a “contains” statement, it’s still important to read through the ingredient label to check for allergens.
Then there’s the precautionary warning. A precautionary warning might look like: “may contain traces of wheat,” “made on shared equipment with sesame,” “made in a shared facility with eggs and milk,” “may contain soy.” These precautionary warnings are voluntary and unregulated. That means if a manufacturer is selling a product that was made on shared lines with milk but milk is not an intended ingredient, for instance, they could 1) add a precautionary warning, 2) NOT add a precautionary warning. In addition, the language in a precautionary warning is not regulated either, and research has not found any consistent differences in amount of an allergen found based on the language used, i.e., a “made in a shared facility” warning is not necessarily more safe than “may contain traces of” warning.

Please see the figure below.

But don’t freak out. This is where the moms on Facebook tell you that choosing foods with precautionary warnings is “like playing Russian Roulette,” which is basically saying one of those items might be a loaded gun that can kill you. Sigh. Based on the evidence-based advice I’ve heard from allergists and academic allergy organizations, there is far more nuance than that. See the sources below to learn more about the actual risks, which are generally low.

I always have to say: Please speak to your board-certified allergist for guidance about how to handle precautionary labeling.

And with that, here’s our journey about how we handled precautionary warnings.

Stage 1: Avoid

At the beginning of our allergy journey with our daughter, I avoided all products that had precautionary warnings with my daughter’s allergens: peanut, dairy and egg.

When she was around 12 months old, we gave her some plain Puffin cereal for the first time. A few minutes later, she had two small hives near her mouth. I looked at the label and realized that there was a “may contain peanut” precautionary warning. She didn’t show any other symptoms, but this solidified my decision not to give our daughter items with precautionary warnings.

A year or so later, I learned that these precautionary warnings were not mandatory or regulated like the main part of the ingredient label was. And this made me think, “Huh. Then that means that a product without a precautionary warning could very well have invisible/trace amounts of allergen in it. The absence of a precautionary warning doesn’t necessarily mean the absence of cross-contact.”

Around the same time, my daughter had two oral food challenges: baked egg and baked milk. For both of these challenges, she had mild reactions at the very last dose. Her allergist made the astute observation that she did tolerate quite a bit safely.

Stage 2: Milk & Egg

All of these things together - her tolerance for a small amount, learning that I may already be feeding her products with some cross-contact, a recent lack of mysterious reactions - gave me the confidence to give my daughter items with precautionary warnings for milk and egg. (We did not challenge the peanut, so I didn’t have any additional data about her threshold for peanut at that time.)

I didn’t give her all of the “may contain egg/milk” products right away. But I picked and chose items of high value - foods that made me think, “It would be so nice to be able to incorporate this into her diet” - foods whose benefit seemed to outweigh the small risk. So one by one, carefully, I began to give my daughter some items that did have a precautionary warning for milk and egg, still avoiding “may contain peanut” items.

To further lower the risk, I made sure to give her these items in the morning (so that I’m not wondering about whether a reaction could start while she’s sleeping) and when she wasn’t sick (a factor that may make someone’s threshold of tolerance lower).

When my daughter was 5 years old, I heard the podcast episode “What Does Precautionary Food Allergy Labeling Actually Mean?” by AAAAI and hosted by Dr. Dave Stukus. It absolutely blew my mind.

Among the many facts the guest, Dr. Kattan, shared, I was astounded to learn that the eliciting dose that causes 50% of people with a dairy allergy to react is about a teaspoon of milk. For those with a peanut allergy, that amount is 2/3 of an entire peanut. (And yes, this also means that the other 50% will react to less than that amount.) See image above to see the amounts of allergens that 50% of people in the study tolerated safely, even while allergic to that food.

Examples of foods measured at the approximate eliciting dose for 50% of people who are allergic. Importantly, half the people with food allergy will be able to ingest more than this amount, including much more.

On top of that, Dr. Kattan shared a study that showed that there was about a 10% chance that a product with a precautionary label had a detectable amount of that allergen. In that same study, there was a 5% chance that a person allergic to that ingredient was sensitive enough to that amount of the allergen to elicit a reaction. And within that 5%, 5% of those people experienced an anaphylactic reaction.

So let’s math that out. If 2,000 people eat this product, then according to that study, 100 people (5% of 2,000) had a reaction. Of those 100 people, 5 people (5% of the 5%) had an anaphylactic reaction. In other words, 1,900 people were not affected, 95 people had a mild reaction, 5 people had an anaphylactic reaction.

From what I was observing about my daughter (and comparing it to stories I was reading on the Facebook groups), it appeared that my daughter may have a higher threshold for her allergens. Maybe I didn’t need to be afraid of invisible trace amounts for any of her allergens.

A lot of this data comes from the incredible research in an article called “Managing Food Allergies When the Patient is not Highly Allergic.”

Stage 3: Peanut

As I was marinating on these thoughts, there happened to be a granola bar that my daughter badly wanted. It had a “may contain peanut” warning, so my daughter knew based on how we’ve taught her before that it wasn’t for her.

But in that moment, I did a quick risk vs. benefit calculation. She really wanted it. It would be great to add this bar to her diet. These bars are often given out at events we go to. And…based on what I was learning…the risk was low. It was early in the day (I didn’t want to take a risk close to bedtime), she wasn’t sick or super physically active (illnesses and higher body temperature with physical activity can lower our threshold for our allergens), so I decided that it would be a good time to give this bar a try.

She ate it. No reaction. She was overjoyed. It was worth it.

Stage 4: So Many More Options

Since then, I’ve been cautious about giving her items with a precautionary warning, but we have added many of these products to her diet.

One thing that I learned from Dr. Kattan in that podcast episode is that research shows that products with precautionary warnings that are made by smaller companies tended to have a higher rate of detectable allergens and that chocolate products with precautionary warnings for dairy are more likely to contain dairy. So I do factor that into my risk vs. benefit analysis.

Why Am I Sharing This?

There is a lot of fear, misinformation and just plain confusion out there when it comes to precautionary warnings. On top of that, there’s also a lot of fear and misinformation about people’s tolerance for cross-contact.

But I want to make it clear:

I’m not telling folks to haphazardly start eating products with precautionary warnings.
I’m not saying that everyone can handle invisible/trace amounts of their allergens.
I’m not saying that all products with precautionary warnings are safe.

But I do want to encourage all of us who manage food allergies to understand that the risks in general are low - not nonexistent, but low. I want all of us to factor in our own/our child’s own individual threshold when deciding how to handle precautionary warnings (and not simply doing what people on Facebook and Instagram are doing). I hope folks to do their own risk vs. benefit analysis, considering all the facts and statistics, and not just the fear.

Last and most importantly, please speak to your board-certified allergist for guidance about how to handle precautionary labeling.

Please leave a comment if this was helpful and follow me on Instagram for more content about allergy-friendly Asian food, advocating for our kids, parenting a kid with food allergies and more expert advice straight from…the experts!

“May Contain”