A sulfate-free shampoo is a shampoo that does not contain sodium lauryl sulfate (SLS). SLS is also known as sodium laurilsulfate or sodium dodecyl sulfate (SDS or NaDS0). It is a popular chemical in commercial hygiene and cleaning products. The chemical is particularly useful in applications where the removal of oily residues is needed. While the sulfates used in hygiene products have not been shown to be carcinogenic, the chemicals can irritate the scalp, excessively strip essential oils, and cause hair to be dry.
People with sensitive skin, or who are allergic to sulfates, may wish to avoid these chemicals. A sulfate-free shampoo would be much gentler on the scalp, and not cause an allergic reaction — unless, of course, the user is not allergic to any other ingredients. Many users report that their hair is much softer and less dry when using a sulfate-free shampoo.
When first using a sulfate-free shampoo, most people often feel as if their hair is not getting clean because sulfates are responsible for creating that thick, rich lather that many people desire when shampooing. This can take some getting used to because the hair will not feel as dried out, and some users may associate that stripped feeling with being clean. The hair will be clean, but will be softer and silkier.
Ingredients that are desirous in a sulfate-free shampoo are glucosides and gylcerine. Glucosides are derived from plants like sugar cane. Glycerine, also an organic compound, is a byproduct of animal and vegetable oils and is a colorless, thick liquid. Baby shampoos uses deyl glucoside because it is very mild. Coco glucoside, an additive derived from fruit sugar and coconut oil, is also a popular glucoside additive used in many skin care products.
SLS is a powerful surfactant. The term surfactant is actually a shortened form of surface active agent — a chemical agent that lowers the surface tension of liquids, to allow them to be spread more efficiently. It basically stabilizes a mix of oil and water through surface tension stabilization.
Shampoos that contain sulfates, and even those that do not, are surrounded by controversy. There are reports that claim sulfates are dangerous. There are also claims that sulfate-free shampoos and conditioners merely replace the missing sulfates with extra ingredients and other potentially dangerous chemicals. The onus is on the consumer to check the labels of any sulfate-free products, and look for natural ingredients.
Sulfate-free beauty products are generally more expensive, and are becoming more readily available. Beauty and bath products that are green — products that do not contain any unnatural chemicals that may be harmful to the environment — have become very popular. Sulfate-free shampoos and conditioners are in greater demand because of environmental concerns, as well as for health reasons.