Eczema Knowledge Hub

If you have eczema, you have probably read something about the gut-skin connection — the idea that what lives in your digestive system can influence what happens on your skin. The science here is genuinely interesting, but it has also attracted a lot of hype. Here is an honest look at what the evidence supports, what it does not, and what that means for you.

What is the gut-skin axis?

Your gut is home to trillions of microorganisms — bacteria, fungi, viruses — collectively called the gut microbiome. This community does far more than help digest food. It plays a central role in training and regulating the immune system. When the balance of gut microbes is disrupted (a state called dysbiosis), the immune system can become dysregulated, producing more inflammatory signals. Researchers have found that people with eczema tend to have a less diverse gut microbiome than those without it, though whether this is a cause, a consequence, or simply an association is still being worked out.^[1]

What about probiotics?

Probiotics — live bacteria taken as supplements or found in fermented foods — have been studied extensively in eczema with mixed results. The short answer: the evidence does not currently support probiotics as a reliable treatment for eczema.

A large Cochrane review (the gold standard for evaluating medical evidence) found that probiotics showed little to no meaningful benefit for people who already have eczema, and could not clearly recommend them as treatment.^[3] The ACE Clinical Guideline on atopic dermatitis, published in February 2026, similarly concludes that probiotics have limited evidence for routine use in eczema management and should not replace established treatments such as moisturisers and topical corticosteroids.

Where the evidence is somewhat stronger is in prevention. Some trials have shown that specific probiotic strains (particularly Lactobacillus rhamnosus GG) taken by mothers during pregnancy and given to high-risk infants in early life may modestly reduce the risk of developing eczema — though even here, results are inconsistent across studies and the effect size is small.^[2]

Why do results vary so much?

Probiotic research is notoriously difficult to interpret because the effects are highly strain-specific and dose-specific. A study finding that one strain of Lactobacillus helps tells you nothing about whether a different strain — or the mixed-strain supplements sold in health stores — will do the same. Age, severity, and the individual's baseline gut microbiome also affect outcomes. This is why broad claims about "probiotics for eczema" are hard to evaluate.

What can you do to support your gut health?

The good news is that you do not need to rely on supplements to support your gut microbiome. Diet is the strongest tool available, and it benefits your whole body, not just your skin.

Eating a varied, fibre-rich diet is the most evidence-backed way to support microbial diversity. Aim for plenty of vegetables, fruit, legumes, and whole grains. Fermented foods like yoghurt, kefir, kimchi, and sauerkraut naturally contain live bacteria and can contribute to gut diversity as part of a balanced diet. Reducing ultra-processed foods and excess sugar, which have been associated with lower gut diversity, is also worth prioritising.

Should you try a probiotic supplement?

This is a question to have with your doctor or dermatologist, not one to answer alone. There is no harm in eating a gut-friendly diet. But before spending money on probiotic supplements:

• Know that the evidence does not currently support them as an eczema treatment — they are not in clinical guidelines as a recommended therapy.
• If you do try one, choose a product with a clearly labelled strain and adequate dosing, not a vague "multi-strain blend."
• Probiotics do not replace moisturisers, prescribed topical treatments, or trigger management. Use them as a potential addition, never a substitute.
• If you are immunocompromised, pregnant, or considering probiotics for a young infant, speak to your healthcare provider first.

The gut-skin connection is a legitimate area of research and it will likely yield more actionable guidance in coming years. For now, the most useful thing you can do is support your gut through diet — and manage your eczema with treatments that have clear, established evidence behind them.