Sun alters good skin bacteria, study warns suntan enthusiasts

2023-08-10 16:43:37

Warning to tanning enthusiasts who are ‘browning’ in the sun on the beach during these August holidays: exposure to UV rays would favor an imbalance in the skin microbiota, i.e. an alteration of the ‘good’ bacteria that naturally cover our skin . The warning comes from a British study by the University of Manchester, just published in the journal ‘Frontiers in aging’.

The researchers studied 21 people: before the holidays, 15 of them had a declared goal of ‘tanning’ while the remaining 6 declared their intention to escape the sun as much as possible. The composition of the skin microbiota of the volunteers was studied before their departure for the holidays, then 24 days after their return and again 84 days later: the scientists were interested (in particular) in the 3 main bacterial populations of the skin, i.e. actinobacteria, proteobacteria and firmicutes. The verdict: After a week of vacation, researchers observed a dramatic drop in proteobacteria in pro-tan vacationers.

“Exposure to UV rays emitted by the sun therefore appears to be harmful to the bacterial diversity of the skin microbiota”, comment the scientists. It is known that this microbial imbalance favors the onset of chronic skin diseases, such as atopic dermatitis, eczema or psoriasis, for example. But this should not create panic: the researchers have in fact observed a reconstitution of the skin microbiota 28 days after returning from vacation.