The eczema-allergy link: everything we know + 4 simple ways to manage eczema

Eczema and allergies are on the rise in the UK. Whether it presents as eczema, hay fever, asthma, or food allergies, these conditions are often connected in ways many people are not aware of.

Research shows that having eczema in childhood can increase the likelihood of developing allergies, asthma, or hay fever later in life. This progression is known as the atopic march.¹

As these conditions continue to rise, understanding how they are linked can help us better support the skin and immune system from an early stage.

What is eczema?

Eczema is an umbrella term for a group of inflammatory skin conditions that cause dryness, itching, and irritation. The most common form is atopic dermatitis (AD).²

Symptoms of AD include:³⁴

Flaky, scaly or crusty skin
Itchy skin
Dry, cracked skin
Skin rashes
Swelling
Raised bumps

AD can look different in different people and appear anywhere on the skin. It is often found on the hands, neck, elbows, knees, ankles and face. It often begins in childhood, but it can also develop for the first time in adulthood.⁵⁶

What causes eczema?

There is no single cause of eczema. Instead, it develops through a combination of genetic, immune, skin barrier, and environmental factors.

Skin barrier dysfunction

Genetics can play a role, particularly mutations in the filaggrin (FLG) gene, which is essential for maintaining skin hydration and barrier strength. ⁷ When filaggrin levels are reduced, the skin becomes more vulnerable to dryness and irritants.

In addition, Th2-driven immune activity in eczema can further weaken the skin barrier. Th2 cells release inflammatory cytokinesthat can reduce filaggrin production and increase inflammation. This creates a cycle of inflammation, barrier disruption, and increased sensitivity.⁸⁹

Skin microbiome imbalance

Research suggests that disruption to the skin microbiome plays a role in the development of AD. Increased abundance of Staphylococcus aureus (S. aureus) and Malassezia spp., and reduced microbial diversity are commonly observed in AD. These shifts in the skin microbiome are driven by factors that impair the skin barrier, such as the filaggrin gene (FLG), which weakens immune responses.¹⁰

Healthy skin also relies on short-chain fatty acids (SCFAs) such as butyrate and propionate, which help maintain pH balance and support immune regulation. Levels of these beneficial compounds are often lower in people with AD.¹¹

Gut-skin connection

The gut microbiome plays an important role in immune balance through the gut–skin axis – you can read more about this here.

When gut bacteria are imbalanced, it can contribute to increased inflammation, reduced SCFA production, and greater immune reactivity. This can influence skin health directly.

Research suggests that gut dysbiosis may contribute to the development and persistence of atopic dermatitis, as inflammatory signals can travel between the gut and skin, and skin inflammation can impact gut microbiome function, leading to a perpetuating cycle that’s hard to break!¹²

Studies also show that reduced SCFAs in the gut are associated with an increased risk of developing AD.¹³

Environmental triggers

A range of environmental factors has been implicated in increasing the risk of developing AD and exacerbating acute flare-ups. These include:¹⁴

Air pollution
Irritants in skincare and household products
Pet dander
Dust mites
Change in temperature
Mould spores

What are allergies?

Allergies are your immune system’s reaction to, normally harmless, substances. People can have allergies to almost anything! Common allergens include:¹⁵

Pollen
Bee stings
Various foods
Dust mites
Medication
Animals

Allergic responses involve a complex immune process. Normally, when your body detects a substance as a threat, it activates B cells, which produce antibodies – this is called sensitisation; a normal immune response. During sensitisation, allergen-specific Immunoglobulin E (IgE) antibodies are produced. On re-exposure, these antibodies trigger mast cells to release histamine and other inflammatory compounds, leading to an allergic reaction.

It is important to note that not everyone with IgE antibodies will develop an allergy. ¹⁶

Once sensitisation occurs, a person can have antibodies for years but only develop the allergy upon re-exposure to the substance. Symptom severity and the type of immune response can vary, ranging from hives to anaphylaxis.

How eczema and allergies are connected

The link between eczema and allergies is known as the atopic march.

AD and allergies often develop in early childhood. An infant’s gut flora is a critical driver for immune system development. This includes the transformation of naive T cells (a type of immune cell) into various T helper cell types, such as Th1, Th2, and Th3.¹⁷ The priming of the immune system is important as Th2 responses play a role in skin barrier function and AD development.

Filaggrin gene (FLG) defects and Th2-driven inflammation impair the skin barrier, allowing allergens to enter the skin when they likely wouldn’t otherwise. This can then lead to sensitisation; the progression of developing an allergy.¹⁸

Gut and skin microbiome imbalances can further amplify immune reactivity and IgE responses, increasing the likelihood of the development of allergic conditions.¹⁹

Preventive strategies (e.g. early emollients, allergen introduction, allergy screening) are under active research, but guidelines stress early food introduction and atopic dermatitis control to interrupt the march.²⁰

Supporting your skin

Kefir + Prebiotic – Emerging research highlights the role of gut health in skin inflammation. Supporting the microbiome may help reduce inflammatory markers associated with atopic dermatitis.²¹ A combined approach using probiotics and prebiotics (synbiotics) can help restore microbial balance. A recent study involving our Kefir and Complete Prebiotic showed a lowering in inflammatory markers such as IL-6 and IFN-γ, after 6 weeks of taking both.²²
Gentle Skincare – Barrier-friendly skincare is essential in eczema management. Our Sensitive Lotion and Sensitive Soap are suitable for those with sensitive, reactive skin, containing no essential oils and only the purest ingredients.
Reducing irritant exposure – Simple environmental changes can help reduce flare severity: avoid harsh cleaning products and fragrances, use gentle, non-irritating skincare, consider air filtration in high-allergen environments and track triggers in a symptom diary.
Vitamin D – Vitamin D plays a role in immune regulation and skin health. Low levels may be associated with more severe eczema symptoms. Supplementing appropriately when you’re low, or over winter, can help improve symptoms.²³

Eczema and allergies are deeply connected through shared immune pathways, skin barrier function, and microbiome balance.

While genetics and environment both play a role, supporting the skin barrier and gut health may help reduce inflammation and improve resilience over time.

Any questions? Contact one of our Nutritional Therapists via live chat, weekdays from 8 am to 8 pm.