Eczema and sun: good or bad idea?

Individuals suffering from eczema are not all equal when it comes to the sun. While some notice an improvement in their skin condition with the arrival of warmer weather, others see their lesions worsen. This is referred to as photosensitive eczema. This is a photo-allergy, meaning a cross-reaction between a product containing an allergenic molecule and the sun's UV rays. It's quite rare, but it does happen.

Phototherapy is sometimes recommended for individuals suffering from eczema. This method utilises UV rays to alleviate the red lesions and characteristic itching of this skin condition. Numerous studies demonstrate its positive effect on eczema . One study, in particular, showed that regular exposure of 29 children to UVB with a restricted range of wavelengths (300-320 nm) for 12 weeks resulted in a 61% reduction in their SASSAD (Six Area Six Sign Atopic Dermatitis) score. This score is often used to measure the severity of eczema.

Another point in favour of the sun: it stimulates the synthesis of Vitamin D . A recent study has shown that Vitamin D increases the production of cathelicidins. These are molecules that act against Staphylococcus aureus, bacteria that sometimes colonise eczema-prone skin. Staphylococci can cause secondary infections of eczema, sometimes with significant consequences. Vitamin D has a protective effect against this. Furthermore, it promotes the production of proteins necessary for the functioning of the skin barrier, which limits dryness and the entry of pathogens.