Episode 51: Will Removing Foods Help Your Child’s Eczema—or Make Things Worse?

Nov 5

Written By Global Parents for Eczema Research

Is allergy testing helpful for eczema? Can some foods trigger eczema and can avoiding those foods make eczema better? Many parents give it a try—but experts say it’s not the right approach. So what’s going on? Are certain foods associated with eczema? We talk to Dr. Matthew Ridd, a leading eczema and food allergy researcher from the University of Bristol, to find out what the science actually says about diet and eczema. If you like our podcast, please consider supporting it with a tax deductible donation. Read the transcript.

EP51: Will Removing Foods Help Your Child’s Eczema—or Make Things Worse?
Lynita: Hello, and welcome to the podcast. Food allergy testing is often used to determine if foods are making eczema worse. Based on the results, parents may cut food from their child's diet in hopes of easing symptoms, but interpreting these tests isn't always straightforward. There's disagreement even among allergists about what actually counts as a positive result.
And here's the surprising part. Research shows that removing those foods rarely improves eczema, yet many parents desperate to help their child still go down that road. I did too, even knowing the evidence, I felt I had to try something. What I didn't realize was food elimination isn't risk-free and it can actually increase the chance of developing long-term serious food allergies.
To help us weigh the pros and cons of food allergy testing for eczema, we're joined by Dr. Matthew Ridd. Dr. Ridd has been at the University of Bristol in the UK for over two decades where he has established a research program focused on managing childhood eczema and food allergy. His landmark trial comparing four emollient types for eczema won the Royal College of General Practitioners Research paper of the year in 2022 for its impact on eczema care. But today we are talking to him about one of his current research projects, which explores whether food allergy testing can actually help bring eczema relief, nicknamed TIGER for short, Dr. Ridd: Welcome to the podcast.
Dr. Ridd: Hello. Thank you for having me.
Lynita: I have a load of questions here for you today, but can you please start by explaining the different types of food reactions we can have?
Dr. Ridd: Yeah, There is a lot of confusion out there around terminology. So, even amongst healthcare professionals terms like allergies and intolerances tend to be used interchangeably, but they are different things.
So when we talk about a food allergy we're talking about something that involves the immune system, and that's conventionally broken down into two types: immediate symptoms, which are your classical eating a peanut and getting symptoms within a few minutes, usually it's fairly obvious the link between the ingestion of the food and the development of the symptoms; and then delayed symptoms, which is what is more commonly talked about, in terms of the topic today, about food allergy allergy testing children with eczema and parents wondering whether it's something their child ate yesterday a couple of days ago that's made the eczema worse today.
Lynita: Right. So just to clarify, we are talking about food allergies today. Which is an immune system reaction to a food that we've eaten, and the reaction can be immediate or delayed. What we aren't talking about today is food intolerance. Which is a digestive system reaction where you might feel bloated or gassy.
Dr. Ridd: Yeah
Lynita: If there is a delay, what sort of length of time would we be thinking? We'll be thinking a few days…
Dr. Ridd: Anything from over two hours to a few days really to the 48, 72 hours is typically the window.
Lynita: Right. How common are food triggers for eczema?
Dr. Ridd: Well it really depends on where you look and how you define it. If you look at the literature, the figures vary quite widely. In general, parents and even healthcare professionals tend to overestimate the true prevalence of food allergy. If you take a population sitting out there in the community then you'd probably get a truer picture. But children with eczema are at higher risk of immediate type food allergies,
Lynita: Do you know if there's any statistics that say how often the food allergy might be picked up for eczema?
Dr. Ridd: Like I said, figures vary wildly. some estimates we'll say 30, 40%, But as I say it really depends on which study you look at, how they've selected that population, and those are the severity of the eczema. So there's quite a lot there, but hopefully that helps contextualize the discussion today.
Lynita: Yes. Sure. And what type of foods would we be most expecting to be triggers for this effect on eczema?
Dr. Ridd: So it's the usual suspects that you, your listeners might have come across cow's milk, hens egg, wheat, soy, peanut, tree nuts, fish and shellfish.
Lynita: Okay, so they're the ones that we would be looking for.
Dr. Ridd: As I say, children with eczema are at higher risk of developing immediate type food allergy, but there's no evidence that children with eczema are more likely to have problems with different foods than any other child, whether that's immediate or delayed.
Lynita: Okay, so what I'm hearing is that kids with eczema are at higher risk of developing food allergies only because their skin barrier is damaged.
Dr. Ridd: Yeah
Lynita: And we know from previous research that food allergens entering the body through the skin are picked up by immune cells in a way that is different from when they're eaten. Which triggers an allergic response.
But coming back to what you were saying, if sensitization through the skin can be avoided by keeping peanut dust out of the house or by always washing hands with soap before we apply moisturizer to our kids, then there's no reason for our eczema kid to develop food allergies.
Dr. Ridd: Yeah
Lynita: Another thing that often happens with very young kids, we discover eczema while the babies are still breastfeeding, they haven't started on solids yet, and now the mother who's already in a challenging circumstance they're now trying to cut food from their diet.
What advice do you have for mothers that are breastfeeding and trying to work out if there's a food that's affecting their child?
Dr. Ridd: Yeah. It's not uncommon at all for breastfeeding moms to modify their diet in the hope that it might help the child's symptoms, be that eczema or colic or other symptoms. In terms of food allergy, there's weak evidence that doing that is helpful. What tends to happen is it tends to put the mum on a very restricted diet. It makes them miserable, and if life isn't hard enough, really looking after your young child with eczema, that just makes it worse.
If you can breastfeed, that's great because all the evidence suggests that's the best way to give your child a good start in life. And obviously there's some women that either can’t start or maintain it. In which case I don't think you need to, you know, be hard on yourself about that, but if it's possible, then that's a great place to be.
Breastfeeding and any association with infant symptoms has been quite controversial. So, ideally in conversation with a physician or or a specialist, if you agree that it's worth trying it, then maybe a trial period of excluding food. But I put that definitely towards the bottom of the list of things to try if you're trying to help the child's eczema.
Lynita: Sure it comes back to the old adages. Look after yourself, and then you're in a better position to look after your child and manage their eczema and their sleeplessness and on and on.
If a parent is considering food allergy testing as an option to help with their child eczema, do you think it's a good idea?
Dr. Ridd: It's a common question. The evidence out there isn't great. What evidence there is doesn't suggest, uh, for the majority of people it's a helpful thing. That's really what we're trying to improve the evidence base around with the Tiger study, which we will come on to.
Lynita: I'm looking forward to asking you more about that. Speaking from personal experience, I had read that food elimination probably wasn't going to be helpful, but I was also at my wit's end. And I thought, if there's even the smallest chance that something's gonna help here, I want to do it. So it's this tricky situation between risk versus, um, reward, I guess.
If a parent does decide they're going to go down the road of doing food allergy testing, is there certain ages that it's likely to be more effective versus actually just harmful because they haven't developed a food allergy yet?
Dr. Ridd: The idea of a test is very tempting, isn't it? Because, otherwise you're working on symptoms and the idea of either a skin prick test or a blood test, which is the most common way that we look at, is attractive, isn't it? 'cause it seemed to be objective.
But again, all tests are are imperfect and the majority of the time we shouldn't be doing food allergy tests without talking to the mom, and the child if they're old enough, first of all to work out whether there's a good reason to be doing the food test. 'cause you can't really interpret it in the absence of knowing whether there are any symptoms, and what the nature of the symptoms are associated with the food. You can't just go testing for every food allergen. You have to have a bit of an idea of whether you think it's one food rather than another food.
And the food allergy tests will only tell you potentially if you're sensitized to that food. So that just means that there might be evidence on the test of a problem with that food, but without putting that together with a clinical picture - basically if there's a history of ingestion and when the child's ingested it, whether there are any associated symptoms, whether that is the meaning of that test really.
I think that's a really key thing.
Lynita: So what I'm hearing is that there's no reason to do food allergy testing if you haven't seen evidence that your child probably has a food allergy. So if you can keep a diary and say, hang on, we ate eggs this day, and then after that we had a flare, then there's no reason to do it.
Dr. Ridd: As I said, I think the challenge is particularly with these delayed symptoms, if a child has more immediate problems with the food that develops within minutes to a couple of hours, usually the associate's fairly clear just from, you know, the parent's observation and the symptoms the child has, it's clearly linked to one food, and a food allergy test can be helpful in confirming that relationship.
The challenge is when there's potentially an interval between the ingestion of a suspected food and symptoms because the delayed symptoms are common, particularly when you've got a really young, nonverbal infant. And the nature of eczema is such as that, your experience and others might be, that you do exactly the same thing one week as you did the previous week. And for some unexplainable reason the eczema's worse and that is the nature of eczema. Again, what evidence there is suggests the majority of this isn't linked to foods, it's just the challenge of the condition.
Lynita: I see.
Dr. Ridd: Consensus is that the best way to try and approach this problem is, as you say, to try and keep a diary to try and spot any associations. If there seems to be one food that's suspected, then without food allergy tests, um, you know, a reasonable approach is to try and take that food out of the diet for two to four weeks.
But really important is to reintroduce it for a couple of weeks. Obviously, this doesn't apply when you've got immediate symptoms. Again, this is delayed symptoms. But essentially if you go down the food allergy test route and you're acting on those tests, that's what you'll be doing anyway, is to be taking foods out and reintroducing them.
And it's important to reintroduce them because many, many parents might take a food out, or if the child's on formula change the formula and they see a change in their child's eczema symptoms, and they think, ‘Oh that must be it.’ But maybe that was just gonna happen anyway. It might just have been a coincidence.
And so only by reintroducing you get a better feel. Again, it's, it's imperfect. It's the limit of the science at the moment. But, that's one way to approach the problem.
Lynita: Right. So to recap, keeping a diary is really helpful to spot a connection between a food and eczema symptoms. Then if you do decide to eliminate a food, it's really important to reintroduce it after two to four weeks to see if it really was having an impact on the eczema symptoms.
And always keeping in mind that often triggers for eczema aren't food.
Dr. Ridd: Yeah, um, guidelines vary, but broadly they'll be similar probably to what we say here in the UK, which is generally to avoid routine food allergy testing unless, it is helpful to support particularly in immediate type food allergy diagnosis. But you might want to consider it where you've got particularly severe eczema that's resistant to usual treatment. and it is that population that are at higher risk.
Lynita: Right. So the guidelines recommend against food allergy testing in the UK. Similarly, both the American Academy of Allergy, Asthma and Immunology, and the American Academy of Dermatology both recommend against food elimination for eczema. I'll provide those links with podcast.
But as mentioned, we parents get pretty desperate and may go ahead with allergy testing anyway, then they come back with some results and they say, ‘Help. I don't know how to interpret these results now.’ How, how can parents interpret these food allergy tests?
Dr. Ridd: Well first of all, don't buy tests over the internet because there are people out there that will offer you tests that haven't been validated. So, organize any tests through a recognized healthcare provider.
And, the results will vary, according to the allergen you use. So if you're doing a skin prick test, for example, you can either literally use an egg, as a means to prick the food into the skin, or you can get commercial kits, with different types of eggs.
And I don't think anyone should be getting tests unless they've got that person then to help interpret them. Because, the majority of general practitioners won't have had training in allergy, and so won't necessarily be very well placed to interpret them either. So yeah, it's a complex field.
Lynita: It is. So you are saying that anyone can sell an allergy test over the internet, but the quality of that test is completely unknown. Whereas a reputable allergist will be using a validated test and they will know how to interpret those tests.
Dr. Ridd: As I say, the idea of an objective test is enticing. But I think if you're then put into a situation where you've got tests for foods that you weren't expecting and in a position of not knowing what to do with them, that's potentially worse, I think. Particularly if that leads to doing multiple food exclusions.
Can I go into the risks of doing that?
Lynita: Yes, please. Yes.
Dr. Ridd: So first of all, it’s difficult if you are trying to take food out, in the short or longer term from your child. You're gonna have to spend a lot of time looking at labels, and then, potentially that has nutritional implications for your child. You need to be thinking about if you're taking something out long term, do they need something else to try and accommodate that? And then, finally, but really importantly as well is: children with eczema have a high risk of developing immediate food allergy, and actually by taking foods out of the diet that they are tolerating in the hope that it will treat the eczema. It might actually then be promoting the immediate type symptoms because they've got oral tolerance to the food. So actually if it's in their diet, try and keep it in their diet.
Lynita: Sure
Dr. Ridd: There's a move to encourage earlier introduction. Particularly there's good evidence around peanut and egg, for example, early in life of children at higher risk, so children with eczema. 'cause there's evidence that doing so can reduce the risk of food allergy later.

Lynita: Hi listeners. I'm adding a post-production note here because brand new research just published reveals that the incidence of peanut allergy in kids has decreased dramatically since the guidelines recommended early introduction of peanut 10 years ago. The change was not so apparent in kids with eczema., So more research is still needed, but this is good news in the food allergy world. And now back to the interview.
Dr. Ridd: Obviously you're not giving children whole peanuts, there's specific advice you should seek around how that's given. The message here is delaying introduction of those two foods in particular and other allergens potentially, or taking those foods out of the diet for a prolonged period when your child was ingesting them without immediate symptoms isn't without risk,
Lynita: So when is the best time for this early introduction of these allergens?
Dr. Ridd: I think the vast majority of children, even those with eczema, can eat all foods. There's good evidence that it's safe and a desirable thing to be introducing, particularly egg and peanut, early in children with eczema. And that's around the four to sixth month.
I think some people are concerned that introducing solid foods for the first time might discourage breastfeeding. The message is still to keep breastfeeding, but consider introducing those foods around that time point and not delaying them.
If you go back a couple of decades, the advice was to delay introduction of foods and that was the wrong advice. But, what evidence there is points to getting the foods into diet and keeping 'em in the diet.
Lynita: Sure. So for example, you might have a breastfed baby, but you could give them a tiny little bit of peanut butter on the end of your finger, just every couple of days or so,
Dr. Ridd: Yeah
Lynita: Okay
Dr. Ridd: It has to be aligned with how the child's developmentally, 'cause there's a certain stage in which children are able to start coping with that already. But, if they're, they're in that four to six month period and they’re looking like they're looking for that, then that's a good thing to do.
Lynita: Yeah, and I think most parents are fairly aware of when their child starts showing interest in food.
Dr. Ridd: Yeah
Lynita: I know I'm asking you specific things, but I know as a parent we want specific answers. We don't want: just introduce them early. You know, it's really difficult to be told things like that.
Dr. Ridd: The context is, as I say, because, you know, I live and work in the UK and the guidance will vary a little bit. So what I don't wanna do is give information, which might contradict what you have in North America to Europe, for example. But, if you look across the guidance, that's a consistent message really around four to six months for those foods.
Lynita: Yeah, yeah, understand. So you should check your guidelines for where you live. And follow the guidelines for your area.
Okay, tell me about the Tiger study that you're conducting currently.
Dr. Ridd: So, uh, this study starts with a question that we started this interview with really, should my child have a food allergy test to help them determine whether a given food is driving the eczema symptoms. 'cause is a question commonly asked.
And if generalists like myself, family physicians, are confused as to what to do, that's not their fault. It's because there isn't good evidence for what we should be advising parents. So, for the last few years we've been running this UK funded, study and we've been recruiting children with eczema three months to two years of age. And then we're randomizing them. So half of the, children and families get standard care. The other half get the skin prick test there and then, to cow's milk, hen’s egg, wheat and soy. And then based on the results of those tests along with the clinical history we give them standard care, and they're also getting some dietary advice as well.
Lynita: Great. And what are you hoping to learn from this study that will make a difference to managing eczema?
Dr. Ridd: So at the end of it, we should have a much better understanding about the value of doing these routine food allergy tests in these children in relation to whether it makes a difference to eczema symptoms.
There may be other useful information we get from the study, part of that relates to this tight rope that we're potentially walking between doing food allergy tests and taking foods outta their diet, which might help their symptoms versus taking foods out the diet that might mean they lose all tolerance to those foods. 'cause the evidence at the moment is all very much pro inclusion. But until we do this study there will still be this wide variation with parents getting different advice from different healthcare providers because people will interpret the evidence more or less well, or parents doing their own thing, without any professional input. So, I'm really hopeful that we'll provide a bit of clarity. We realistically will not answer all the questions around it, but we should improve the evidence base in this area.
Lynita: As a parent, I'm really pleased that you're doing the study, because this is the question that I faced: do I go down this road even though it's hard to do all this testing and eliminate foods and what is going to be the negative effect if I do? I think it's gonna help parents make decisions about how to manage eczema.
So thank you for answering, try trying to answer the question.
Dr. Ridd: No, happy to try and move the evidence forward in this area. And, although it's being conducted in the UK, hopefully the findings will be relevant to any parent of a child with eczema.
Lynita: Thank you. Is there anything else you would like to add before we wrap it up?
Dr. Ridd: Yeah. If parents are interested in the study, We're just finishing recruiting our last children now. So around 500 children. And we're gonna follow all these children up for nine months. So, by the time we've followed the last child to come into the study, the results probably won't be available until late 2026. Which I know seems like an awful time away, but, better to do a study properly and get a decent answer than to try and rush it really.
And you can find out more about the study at www.bristol.ac.uk/tiger-study and you can also find links from there to other research we're doing around early food introduction and food allergy in children.
Lynita: Fantastic, and I'll include that link in our information that we put out with the podcast.
But thank you so much Dr. Ridd. I really appreciate your time today and sharing your information with us.
Dr. Ridd: Pleasure. Thank you.