November 2006
Dear Paula,
Although silicones themselves may not cause a scalp allergy, the sulfates required to remove them can. I know several people who cannot use sulfates, and therefore silicones, due to allergies. Silicones are only part of the equation. The real problem comes from using harsh sulfates, which are necessary to remove non-water-soluble silicones, not the silicones themselves. It is important to note that if one is not using sulfates, they should not be using silicones (unless they are water-soluble) because silicones will build up on the hair unless removed with sulfates. They also prevent moisture from reaching the hair, as well as causing numerous problems due to buildup, like frizz or dullness. I would suggest your readers check out the www.naturallycurly.com message boards. Many women on that site have no-sulfate, no-silicone hair routines for different reasons, including scalp allergies due to sulfates. Thank you to taking the time to read my input!

Lara, via email

Dear Lara,

Sulphates in and of themselves are not inherently “harsh.” The harshness depends solely on which ones are being used and in what combination. And all silicones are non-water-soluble—there are no exceptions. Some are “heavier” than others, but their physical properties remain consistent, whether you see them listed as dimethicone, cyclomethicone, phenyl trimethicone, and so on. They don't rinse away (in fact they repel water, but water isn't all hair needs to retain moisture), and they are all removed the same way, with detergent cleansers, whether they contain sulphate or not. Sulphates are not required to remove silicone. You can wash your hands with soap and remove silicone from your hands and soap doesn't contain sulphates. If there are shampoos out there that don't use sulphates, that's fine, but assuming they are gentle because they don't contain “sulphates” would be false. Silicones do not block moisture from hair. Quite the contrary: you can put an entire container of silicone on your hair and stand out in the rain and your hair will still get wet, and humidity will absolutely get through (and cause frizz). Silicone is not impervious to moisture. Silicone's ability to allow moisture and air in and out is one of its superior properties, and is also why silicone is used to minimize the appearance of scars (i.e., with silicone bandages). Also, someone who thinks they are allergic to a shampoo would not know whether the allergy was due to sulphates or to the fragrance in the shampoo. Finally, not all sulphated cleansing agents are identified as such, which makes shopping for a sulphate-free shampoo tricky.