A recent article published in ScienceDailystates that new research at the University of Bath (England) suggests that using emollient creams that contain SLS to relieve the symptoms of eczema could actually make the condition worse.
The study, published in the British Journal of Dermatology, shows that aqueous (a parafin-based emulsion) creams reduce the thickness of healthy skin over a period of four weeks, calling into question whether the creams should be used for treating eczema.
Originally used as a wash product, aqueous-based creams are currently the most widely prescribed emollient for the treatment of dry skin conditions. They are used to moisturize the skin, improving flexibility and preventing cracking in the protective outer layer, called the stratum corneum.
However, the creams contain a detergent, called sodium lauryl sulphate (SLS), which can increase the permeability of the skin barrier and cause irritation.
The study found that when healthy volunteers applied the cream to their forearms daily for a period of four weeks, the thickness of the stratum corneum was reduced by more than ten per cent.
The researchers anticipate that using this cream would have an even more dramatic effect on damaged skin such as that found on eczema sufferers.
Richard Guy, Professor of Pharmaceutical Sciences at the University and Project Supervisor, explained: “The skin has a protective barrier layer of lipids, around one eighth the thickness of a sheet of paper, that stops chemicals from getting into the body and keeps moisture in.
“SLS is a detergent used to mix oils into aqueous-based moisturisation creams to give a nice creamy texture. It’s also used widely in shower gels and other cosmetics.
“Our study has found that rubbing aqueous creams containing SLS into the skin thins this protective barrier, making the skin more susceptible to irritation by chemicals.
“So to use this cream on eczemous skin, which is already thin and vulnerable to irritation, is likely to make the condition even worse.”
The study suggests that “it might be better for eczema patients to use oil-based ointments on damaged skin.”
To read more about the study, click here:http://www.sciencedaily.com/releases/2010/10/101018074536.htm
To read our recent blog post about the dangers of SLS, click here:http://www.seaweedbathco.com/blog/avoid-sls/