Hair loss is frustrating and scary. Often times the reasons are genetic or hormonal which makes it hard to resolve. But there are many causes for temporary hair loss including iron deficiency, medications, hairstyles etc. One hair loss trigger that we rarely suspect is the misuse of shampoos.
Could your shampoo be a hair loss trigger?
Improper use of shampoos containing strong surfactants like sodium lauryl sulfate (SLS) can lead to hair loss, according to the National Toxic Encephalopathy Foundation. They state that hair loss can be the result of poor rinsing that leaves SLS deposits in your hair follicles.
This surfactant, along with most charged surfactants, can adsorb to skin protein causing them to denature (alter the natural qualities) and swell (Ref:Handbook of Cosmetic Science and Technology, Third Edition). The extent of this denaturing process is dependent on the concentration and time of exposure to the skin. Thus deposits from harsh shampoos can corrode the protein in hair follicles over time, cause scalp irritation and inflammation, and eventually cause hair loss.
Hair loss shouldn’t result from shampooing if hair is rinsed properly. Deposits of surfactants left behind can however be harmful.
Strong surfactants tend to clean very well and can end up removing too much sebum from the scalp. This causes the scalp to dry out, flake and itch. Itchy scalps can be another hair loss trigger due to the mechanical removal of the hair fibers during the itching action.
So if after shampooing, your scalp gets sensitive, check your shampoo. The surfactants might be the reason. Skin changes over time, and it might have become less tolerant to the strong surfactants. [Also make sure your hair products are not expired.]
Not all sulfates behave similarly. The ethylated versions of SLS, such as sodium laureth sulfate (SLES) or ammonium laureth sulfate are milder. Unfortunately many people have bundled all the sulfates into the same basket.
Some examples of mild surfactants: sodium cocoyl isethionate, cocamidopropyl betaine, Disodium Laureth Sulfosuccinate, sodium cocoyl glycinate etc.