Sodium Lauryl Sulfate (SLS) and Propylene Glycol (PG), most likely.
These common ingredients found in most drugstore shampoos and conditioners may seem harmless, and save you money, but they might be costing you something else. Sodium Lauryl Sulfate or SLS can cause blindness and lead to the formation of cataracts. Since SLS penetrates the brain, eyes and liver and remains in those areas long-term it can retard the healing process of certain cells and even degenerate them. For example, eyes that incur cell damage would not be able to heal properly while SLS is in the system. According to the Material Safety Data Sheet (MSDS) used by the US government, SLS can also cause burning sensations, wheezing, coughing, shortness of breath, nausea and vomiting.
Propylene Glycol is a chemical derived from petroleum; it can be found in most shampoos and conditioners of a pharmaceutical grade. Industrial grade PG is present in anti freeze, paint, laundry detergent and de-icers. While the jury is still out on exactly how harmful the pharmaceutical additive is to the human body long term, during testing with the Cosmetic Ingredient Review Panel, it caused eczema and skin irritation in 50% of the participants who used it. Cases of liver, skin, and kidney damage were also reported by the MSDS.
It is a personal rule of mine to avoid SLS (and any cousins of SLS) products, and I don’t see much difference in the performance of SLS-free versus consumer brands with sulfates. The cleaning power is just as good, and much less damaging for my totally chemically damaged hair. Try a few natural shampoos and conditioners to keep your insides as healthy as your outside.
An added bonus of using SLS free shampoos is that perms and Brazilian blowouts last longer, and hair is less dry and frizzy over time with repeated use, so what’s the harm? Try a few of these SLS and PG free shampoos and conditioners in lieu of standard popular brands (most are pretty cheap) :
Next time you are about to pick up that economy sized bottle of shampoo or conditioner, take a quick perusal of the ingredients, you may be enlightened!