What causes eczema? © Getty Images

What causes eczema?

Although not fully understood, the answer could lie in its genetic link to both asthma and food allergies.

Asked by: Don Leung, Twickenham


Although it’s common, eczema is not fully understood. It often has a genetic basis and around one-third of children with eczema also have food allergies and many have asthma. Sufferers have an overactive immune system, which responds aggressively to irritants. Eczema can also be caused by an abnormal immune response to bodily proteins.

Flare-ups have a wide range of causes, including heat, soap, skin products, and illnesses such as the common cold. A UK team from Newcastle recently came a step closer to an effective treatment, after identifying how a skin barrier protein called filaggrin affects eczema pathways.


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