Thanks for taking the time to answer all these questions! It’s a wonderful resource.
I belong to a long hair site where there are a number of fanatics who insist that, among other things, -cones (silicone, dimethicone, amodimethicone) are terrible for your hair. I know that you answered a fairly similar question already, but I’d like to be able to give a detailed response to their claims that it a) locks out moisture, b) makes it difficult to see and thus, trim split ends and c) is extremely difficult to remove from hair without stripping it totally dry.
Thank you for any help you can give!
The Left Brain Responds:
Jessica, thanks so much for being a truth-seeker!
First, just to set the record straight, “silicone” is the category which covers the ingredients you asked about. Dimethicone is one type of silicone, amodimethicone is another. Cyclomethicone is another. Because of their different chemisty, these silicones have very different properties and can be used in different types of products. So, not all silicones are created equal.
Now, let’s deal with your specific questions:
a) Do silicones lock out moisture?
Yes they can, but they can also lock it IN. Dimethicone in particular, is good at forming a barrier film that can help waterproof your hair. That’s a good thing because you want to lock in hair’s natural moisture but you also want hair to have some resistance against humidity which is one of the major causes of frizz. So, the “myth” you asked about is true, but it’s not necessarily a bad thing.
b) Do silicones make it difficult to see split ends so you can’t trim them? Yes, silicone products (espeically silicone serums like Frizz-Ease) do smooth over split ends to make them less visible. THEY ARE SUPPOSED TO! That’s the point!! If you want to trim your split ends you should do it either BEFORE you apply a silicone serum or AFTER you wash it out of your hair. Which brings us to your final question…
c) Is silicone extremely hard to wash out of hair without stripping it dry? Under most circumstances silicones will wash out of your hair without much problem. But if you’ve applied multiple products containing high levels of water insoluble silicones, your might have to lather, rinse, repeat before you get it all out. In most cases, the protection you get from using silicones out-weighs the damaging effects of washing them out.
The Brains Bottom Line:
Despite what stylists and other non-scientists may tell you, silicones are one of the most effective conditioning ingredients you can use on your hair. Period. We defy anyone to present data to the contrary.