The Connection Between Atopic Dermatitis (Eczema) and Developing Food Allergies Later
If you or your child has been living with atopic dermatitis and food allergies, you may have noticed that one condition rarely seems to travel alone. The relationship between eczema and the later development of food allergies is well-documented in clinical literature — and understanding this connection can be a meaningful step towards managing your overall health more proactively.
This article explores what current research suggests about the atopic march, how skin barrier dysfunction may influence immune sensitisation, and who may benefit from structured food allergy testing.
What Is Atopic Dermatitis, and Why Does It Matter for Allergy Risk?
Atopic dermatitis (eczema) is a chronic inflammatory skin condition characterised by itchy, dry, and irritated skin. It affects approximately 1 in 5 children and around 1 in 12 adults in the UK. Beyond skin discomfort, atopic dermatitis is widely regarded as the starting point of what clinicians refer to as the "atopic march" — a progressive sequence in which one allergic condition may predispose an individual to developing others over time.
Definition Snapshot: Atopic dermatitis is a chronic, immune-mediated skin condition that disrupts the skin's natural barrier. This disruption may allow environmental allergens to enter the body through the skin, potentially triggering IgE-mediated immune responses that can manifest as food allergies, allergic rhinitis, or asthma later in life.
The Atopic March: Understanding the Progression from Eczema to Food Allergy
The atopic march describes a pattern observed in clinical and epidemiological studies, whereby atopic dermatitis in infancy or early childhood is associated with an increased likelihood of developing food allergies, asthma, and allergic rhinitis as a person ages.
How Skin Barrier Dysfunction May Play a Role
The skin's outermost layer, the epidermis, acts as a physical and immunological barrier. In individuals with atopic dermatitis, genetic mutations — particularly in the filaggrin gene — can impair this barrier function. When the skin barrier is compromised:
- Allergens such as peanut proteins, milk proteins, or dust mite particles may penetrate the skin surface
- The immune system may encounter these allergens in a sensitising context
- The body may produce specific IgE antibodies in response
- Subsequent exposure to these allergens through ingestion may then trigger an allergic reaction
This transcutaneous (through-the-skin) sensitisation pathway is now considered a significant contributor to food allergy development, particularly in infants and young children with moderate-to-severe eczema.
Practical Insight: Not everyone with eczema will develop food allergies, and not everyone with food allergies has eczema. However, the presence of early-onset, persistent atopic dermatitis may suggest a heightened immune sensitivity that warrants closer attention.
Who Is Most Likely to Experience This Connection?
Understanding the risk profile can help individuals and families make more informed decisions about proactive health screening.
Individuals Who May Benefit from Allergy Blood Testing
- Infants and children with moderate-to-severe atopic dermatitis diagnosed before 12 months of age
- Adults with long-standing or poorly controlled eczema who experience unexplained digestive symptoms or facial swelling after eating
- Individuals with a family history of allergic conditions (asthma, hay fever, food allergies)
- People whose eczema flares appear to correlate with specific foods or dietary changes
- Those who have noticed oral allergy syndrome symptoms following the consumption of certain raw fruits or vegetables
If you are based in London or the surrounding areas, private allergy blood testing offers accessible, timely results without lengthy waiting periods. Our nurse-led clinic at The Allergy Clinic provides a range of structured testing options designed to support your health awareness.
Eczema and Food Allergies: Key Differences and Overlaps
Understanding how these two conditions relate — and differ — can help contextualise test results and health decisions.
| Feature | Atopic Dermatitis (Eczema) | Food Allergy |
|---|---|---|
| Immune mechanism | Th2-driven chronic inflammation | IgE-mediated acute immune response |
| Primary symptom | Itchy, dry, inflamed skin | Hives, swelling, digestive symptoms, anaphylaxis |
| Trigger type | Environmental, stress, skin irritants | Specific food proteins |
| Onset | Often in infancy; may persist into adulthood | Can develop at any age; often linked to prior sensitisation |
| Detectable via blood test | Elevated total IgE, eosinophils may suggest atopic tendency | Specific IgE food panels can indicate sensitisation |
| Connection | May predispose to food allergy via transcutaneous sensitisation | Often coexists with or follows atopic dermatitis |
What Allergy Blood Tests Can Reveal
Allergy blood testing measures the presence and levels of specific IgE (sIgE) antibodies in the blood. Elevated IgE responses to particular food proteins — such as peanut, egg, milk, wheat, soy, tree nuts, or shellfish — may suggest sensitisation to those foods.
It is important to understand that:
- A positive IgE result indicates sensitisation but does not automatically confirm a clinical allergy
- Results should always be considered alongside symptom history and clinical context
- Testing is most informative when used as part of a broader health awareness approach
Our clinic offers food allergy blood testing using trusted laboratory analysis, with clear, professionally reported results to help you have more informed conversations with your healthcare provider.
Practical Insight: IgE blood tests provide a valuable layer of information. They can help identify whether your immune system may have been sensitised to specific foods — even before obvious allergic reactions have occurred.
How Often Should You Consider Allergy Testing?
There is no universal recommendation for routine allergy testing in asymptomatic individuals. However, structured testing may be worth considering:
- Initially, when eczema is moderate-to-severe and food triggers are suspected
- Every 12–24 months in children with known food sensitivities, as reactivity patterns can change with age
- In adulthood, when new or worsening digestive, respiratory, or skin symptoms appear alongside existing atopic conditions
- When planning dietary changes or introducing new foods into the diet of an atopic child
Testing frequency should ultimately be guided by your symptoms and discussed with an appropriate healthcare professional.
Understanding Your Results: What May They Suggest?
Receiving allergy test results can feel overwhelming without context. Here is a general guide to interpreting IgE-based findings:
- Low or undetectable sIgE: May suggest lower likelihood of sensitisation to the tested allergen
- Mildly elevated sIgE: Can indicate sensitisation, though clinical relevance varies; not always predictive of symptomatic allergy
- Moderately to highly elevated sIgE: May suggest a more established sensitisation that warrants further discussion with a healthcare professional
- Elevated total IgE with normal specific IgE: Sometimes seen in atopic individuals and may highlight a general atopic tendency
All results from our clinic are accompanied by a professionally prepared report to support your next healthcare conversation.
Local Relevance: Allergy Testing in London
For residents across London, accessing timely, nurse-led allergy blood testing has become increasingly straightforward through private health screening clinics. Whether you are in Central London, North London, South London, or the surrounding areas, private testing can offer:
- May offer faster turnaround compared to NHS waiting periods in some cases
- Flexible appointment scheduling
- Clearly reported results from accredited laboratories
- Professional guidance on next steps in a supportive environment
You can explore our full range of allergy and intolerance testing options and find out how our nurse-led team can support your health awareness goals.
Frequently Asked Questions
1. What is the connection between atopic dermatitis and food allergies?
Atopic dermatitis (eczema) may disrupt the skin's natural barrier, allowing food allergens to enter the body through the skin and trigger immune sensitisation. This process, known as transcutaneous sensitisation, is thought to contribute to the development of food allergies — particularly in children with early-onset or moderate-to-severe eczema.
2. Does everyone with eczema develop food allergies?
No. While atopic dermatitis is associated with an increased likelihood of developing food allergies, many individuals with eczema do not go on to develop them. The risk may be influenced by factors including eczema severity, age of onset, genetic profile, and environmental exposures.
3. Can adults with eczema develop food allergies for the first time?
Yes, food allergies can develop at any age. Adults with long-standing atopic dermatitis who notice new digestive symptoms, hives, or other reactions after eating certain foods may benefit from structured allergy blood testing to investigate potential sensitisation.
4. What does a food allergy blood test involve?
A food allergy blood test measures specific IgE antibody levels in the blood in response to particular food proteins. It is a straightforward blood draw, typically reporting results within a few days. Our clinic provides food allergy testing with professionally reported results.
5. Can allergy blood testing diagnose atopic dermatitis?
Allergy blood testing cannot diagnose atopic dermatitis, which is a clinical diagnosis based on skin examination. However, testing may reveal elevated total IgE levels or specific food sensitivities that are commonly associated with atopic conditions and may provide useful supporting information.
6. What foods are most commonly associated with eczema flares?
Research suggests that dairy, eggs, peanuts, soy, and wheat are among the foods most frequently associated with eczema exacerbations in children. In adults, the picture can be more varied. Blood testing may help identify whether specific food sensitivities are present.
7. Is allergy testing suitable for children with eczema?
Allergy blood testing is generally considered safe and appropriate for children. If your child has moderate-to-severe eczema and you suspect food triggers may be involved, testing may provide useful information. We recommend discussing appropriate next steps with a healthcare professional following any test results.
8. How is food allergy testing different from food intolerance testing?
Food allergy testing measures IgE-mediated immune responses — the type associated with classical allergic reactions. Food intolerance testing may assess different immune or digestive pathways (such as IgG responses). The distinction matters when interpreting results and considering their clinical relevance. You can learn more on our allergy vs intolerance page.
9. Can I book allergy blood testing in London without a GP referral?
Yes. Our nurse-led clinic in London offers self-referral allergy blood testing, allowing you to access testing without needing to see a GP first. Results are reported professionally and can be shared with your healthcare provider if you choose.
10. What should I do if my allergy blood test comes back positive?
A positive result should be discussed with an appropriate healthcare professional who can consider it alongside your symptoms and health history. Our clinic provides a clearly written report to support this conversation. We do not offer diagnosis, treatment, or prescriptions — our role is to provide accurate, professionally reported testing.
Take a Proactive Approach to Your Allergy Health
Understanding the relationship between atopic dermatitis and food allergies is an important step in taking ownership of your long-term wellbeing. Whether you are managing eczema yourself, supporting a child with a skin condition, or simply curious about your immune health, structured allergy blood testing can provide a meaningful layer of clarity.
At The Allergy Clinic, our nurse-led team is here to support your health awareness through professional, accessible, and clearly reported testing — without pressure, without urgency, and without unnecessary complexity.
Explore our allergy testing services and take an informed step towards understanding your health.
