A recent research undertaken by scientists at the University of California, San Diego, has revealed that keeping the skin too clean might affect its ability to stay healthy and heal itself, as normal bacteria living on the surface of the human skin play an important role in fighting inflammation. These bacteria help bring down the over-active responses of the immune system which could lead to rashes or result in cuts and bruises becoming even more swollen and painful.

Study leader Professor Richard Gallo said, "These germs are actually good for us", while stressing that the new findings could further support the "hygiene hypothesis". First brought to light in the 1980s, the theory says that exposure to bacteria during early childhood could "prime" a person's immune system to prevent various allergies.

While it is true that skin bacteria include some staphylococcal species which actually contribute to inflammation when they are beneath the skin's surface, the study has revealed that these do not trigger inflammation when on the epidermis, the skin's outermost layer. In fact, these actually reduce it.

Details of the study will be published online in the advance edition of Nature Medicine. The findings are expected to give scientists a basis to develop new treatments for inflammatory skin diseases.