How to Trial Foods With FPIES

One area of FPIES that holds a significant amount of confusion and fear is the area of food trials. Choosing new foods to try can feel like a twisted game of Russian Roulette, and it’s especially scary when you’ve seen your child vomit uncontrollably and go into shock. So how do you trial new foods for a baby or child with FPIES?

There are several different ways of approaching food trials, and different approaches might need to be tried before you figure out what works best for your child. Many providers recommend introducing one food at a time, and slowly building up the amount of food given over a period of several days.

In some cases, the child won’t react to the food until after there has been a break in the exposure to that food. For these children, some providers will recommend feeding one food for several days, then taking a small break from that food, eventually reintroducing it to watch for a reaction.

Another method is to feed the same food continuously for a long period of time (six months or more) with absolutely no break. This can be helpful for children that react to many or most foods after having a break in exposure. The idea behind this method is to get the child’s system used to having the food every day so that when it is reintroduced it isn’t perceived as a threat.

Regardless of which method you choose to try, the most important thing is to work with your doctor to determine what patterns, if any, your child has with their reactions. This can help determine the steps to follow for trialing new foods and reintroducing past failed foods.

What are Food Trials Anyway and Why Should I Worry About Them?

FPIES is a non-IgE mediated food allergy that causes problems in the digestive tract for people who have it. Because the condition is fairly “new”, there is not a ton of research on it and there are still lots of unanswered questions surrounding many aspects of the disease. 

If you are one of the lucky few who have a child diagnosed with FPIES before they’ve had any type of extreme vomiting reaction, or one of those blessed mamas with a baby who only reacts to one or two foods, you may not be too worried about food trials and that’s ok. There are some amazingly intuitive, well read doctors that can connect the dots and recognize even the chronic symptoms of FPIES and give a diagnosis and plan of action even at the first appointment. There are also some babies that may only react to one or two foods, and other than that they are on a normal diet.

 However, there are quite a few people who have children with violent reactions, or babies with very few or no safe foods. In those situations, it’s really smart to have a consistent plan for trying new foods so that parents and providers can look for patterns and learn what to expect from their child’s food reactions. 

There is a difference in a food trial and a food challenge. In this post we are just talking about food trials, which is basically just a way to informally test new foods at home one at a time so that you know if it’s causing a reaction or not. Sometimes, families only need trials to retry foods that their child has failed in the past. Other families use food trials every single time they try a new food for their child, because their child reacts to a wide variety of foods or they have a large number of trigger foods that cause symptoms. 

Food challenges are more structured way to retrial foods that have previously caused bad reactions. These are usually scheduled in a doctor’s office or as an inpatient or outpatient hospital stay. Food challenges can be a long process where you stay for several hours or even for an entire day and eat small amounts of trigger foods as the day goes on. The amount of food eaten increases slowly until it reaches a full serving. The food is considered a pass if there is no reaction in the office, and it’s considered a fail if the child becomes sick or starts vomiting. The benefit of doing these types of challenges in the hospital or doctor’s office is that if there is a reaction, there are trained professionals nearby who are monitoring your child. Sometimes for inpatient food challenges there will be an IV placed before the food challenge begins so that if the child needs medicine or fluids they don’t have to try to place an IV while they are vomiting or dehydrated. 

How do we trial new foods?

This is the million dollar question, and it’s one of the most commonly asked questions about FPIES. It’s also pretty specific to most families, meaning that not everyone trials foods the same way. Honestly, just knowing how others do food trials can give you confidence to try new foods, but it doesn’t guarantee that picking any of these methods will work for your family. Learning your child’s reaction pattern will help you adjust your food trials accordingly. 

As per usual, my disclaimer is that I’m not a doctor, nor do I have formal medical training. I do have kids with FPIES and I’ve been walking this road for four years now, and I’ve been really blessed to learn from some great doctors and from other mamas that have walked down this road before me. Please take everything you read here with a grain of salt, knowing that FPIES is a different beast for each child, even children within the same family. It’s up to you and your doctor to decide what could work for your child, and it may take some trial and error to figure it out. 

So, with all of that being said, there are a variety of different methods for food trials, and you may have to use more than one approach or a combination of methods for your child.

  1. Build-Up Slowly

This method is probably the most common. It starts out with offering a tiny portion of the food that you want to trial. A good starting point is somewhere around ¼ tsp or ½ tsp. Then, you wait and see if there’s a reaction. This can be anywhere from 1 hour after eating up to the next day, it just depends on your child’s reaction pattern. Most commonly I hear people report 2-4 hours. If not, you can offer a little bit more of the same food the next day. If you started at ¼ tsp on day one, you might bump it up to ½ tsp on day 2. At this point you aren’t giving any other new foods or doing anything different – that way if there is a reaction, you can (hopefully) tell it’s from the new food that you are trialing. Every day you bump up the amount of food you are giving by a little bit until you’ve reached a normal portion size and you’ve passed the point at which your child would normally react. If at any point your child starts to react, you can either back it down to the last serving size that worked without causing a reaction, or if you see major fail symptoms (vomiting/diarrhea) then you can consider that food a fail. Some families do 5 day trials, some do 7 days, and some do longer trials of 14 days or more. If you know your child always reacts on day three, then you might be able to do five days of trials and then move on to a new food. If your child reacts on day 10, you might want to trial foods for 12 days or more just to be sure it’s a pass.

2. Take a Short Break

Another method some families use is to build up the amount of food they give, then take a short break for a day or a few days. Then they reintroduce the food and watch for a reaction. Some kids seem to react to foods more after they’ve had a break in exposure. Again, the timing on this will vary depending on what sort of pattern your child shows with their reactions. 

3. Don’t Take Any Breaks

Another method is to add in a food slowly until you’ve worked up to one portion size, and then give that food consistently every single day for several months so that there are no breaks. The idea is to get the body used to getting the food every day so that there are never any lost foods.

 However, there are a few issues with this method. First, it’s really hard to keep up. It’s hard to give the same food every single day for months at a time and never ever miss a day. Sometimes there are unavoidable issues – like the grocery stopped carrying the only brand of the certain kind of milk you are supposed to give every day for the next six months, or your baby suddenly grew tired of eating only ground beef every day in the middle of month five. When you hit these scenarios, if it’s a food they are going to fail, it’s harder to figure out which food caused the reaction because you usually have other safe foods by that time. A second issue with this method is that when you get a lot of safes, it becomes virtually impossible to make a bunch of foods every single day and keep them interesting enough for your child to eat. 

4. The Rotation Diet 

This method is totally off the rails compared to the ones above. On a rotation diet, the whole goal is NOT to serve the same food over and over. This one isn’t used widely because it’s really hard to figure out which foods caused a reaction. It’s also hard to keep up with which foods you’ve served on which days and to make sure that none of them are served on consecutive days. You definitely need some sort of calendar or app to keep track of this. 

We used a rotation diet for several months for my son with moderate success. For us, it worked really well, until it didn’t. Then we crashed and burned. He’s always been my child that will have a period where he does great and passes lots of new foods, then he will get sick and lose most or all of the safe foods he gained. For a long time, we were starting over from scratch with no safe foods every few months. Our nutritionist was the one that suggested this method for us just to see if we could trick his body into accepting some new foods. We tried all kinds of new things, and it went surprisingly well for about 2-3 months each time we tried it. We would gain a lot of safe foods and then it was like his body had enough of trying a bunch of new things and he would start getting really sick from a lot of the new things we had been trying. It was amazing while it worked, but once he started failing foods it was really hard to figure out which ones were making him sick. Still, I don’t regret trying this method with him because we did gain some really stable safes this way that somehow lasted. We also gained some fun foods like fruit snacks and corn chips that I probably wouldn’t have even been trying with him if we were doing full week long food trials (because who is seriously going to waste a whole week trialing fruit snacks when you need things like green veggies and fruits in their diets?). 

How do I know for sure if a food is “safe”?

There are a couple of things to remember when trying to figure out if a new food can be considered safe. 

  • First, what is considered a fail can differ from one family to another. Some families see success pushing through some minor symptoms like reflux, extreme gassiness, or rashes. Other famillies call a food a fail when they start to see specific symptoms like rashes or aggressive behavior because they know it usually ends up as a massive fail with vomiting for their child if they try to push through. Life with FPIES is very tricky because sometimes symptoms that aren’t a big deal for one family can be a warning sign that things are about to get really bad for another family. You just have to watch your child and see what symptoms are at your breaking point where you just call it a fail and move on. 
  • Similarly, each family will probably have to decide for themselves when they feel a food is safe. If you know your child reacts on day 2-4 of a trail and you make it to day 7 with no reaction symptoms, that might be safe for you. If you have a child (like I did) that sometimes reacts on day 4, sometimes reacts two months in, and any number of possible days in between, it might be several months before you decide that food is truly safe. It doesn’t mean that’s going to be the only food you can try for several months, it might just mean you keep a mental note that ___ (insert questionable food here) is a potential trigger and if your child gets diarrhea out of nowhere one day, it’s your most likely culprit.

One of the best things to do when you are starting food trials is to keep a food journal. This can really help you spot patterns of when your child starts to react to foods and what types of foods they are more likely to react to. When we first started out with FPIES, it was easy to keep it all in my head. I had one baby, she ate peas for lunch, then just had formula. But when we started gaining a few safe foods, it got really hard to remember what I had fed for lunch vs what was for snack, and how much she ate of each thing. Then I was trying to keep up with reaction symptoms etc all at the same time. It was very overwhelming. Writing it all down was easier than I thought it was going to be and it definitely helped me figure out what foods were causing issues way faster than before when I was relying on my memory and just guessing. 

  • What about “guaranteed safes” or “free pass” foods like spices and oils?

    This is one thing I hear a lot of from people who are new to life with FPIES. I think it comes from doctors when they are first given their diagnosis. A commonly repeated thought in the medical community is that when foods are refined, some of the protein structure of foods is broken down and the likelihood of that food causing an allergy is lower. I’ve heard doctors say things to us like “you can’t be allergic to oils” or “don’t worry about soy lecithin because the proteins are broken down”. 

This may be true for your child, and I hope it is. However, for a large number of FPIES families, reactions can still happen to oils, refined foods, and even foods we would normally take for granted like spices and seasonings.

My best advice for FPIES is to trial EVERYTHING. At least until you know if your child is going to be someone that reacts to a lot of foods or to just one or two. We realized that a lot of spices were ok in our house, so we started doing shorter trials (just one or 2 days) for those. I still found several that my kids couldn’t tolerate, like sage and cinnamon. 

When we were starting out for my daughter, I trialed tomatoes and zucchini. I thought that since both were ok, I would make spaghetti for her with zucchini noodles. I used a store-bought sauce, and about 4 hours later, BOOM. Reaction. 

I had to dig the sauce container out of the trash, and then try to analyze all 24 ingredients to figure out which one might have been the culprit. I was afraid to try mushrooms, basil, garlic, onions, oregano, olive oil, bell peppers, etc, etc. It turned out to be the peppers, but I didn’t figure that out until 2 more reactions had passed. If I had tried them all individually or even 2 things at a time, it would have been much easier to figure out.  

Bottom line: nothing in FPIES is guaranteed. Be thankful when you find what works but tread carefully until you know it does.