I have highlights and haven't found that CK lightens me any. Even though it's only highlights, my overall natural color gets lightened a little as well. And having naturally dark brown hair, there's actually quite a bit of red in it.

My hair likes glycerin and I've used several products with it in them. I will say that by the time I'm ready for highlights again, they're quite a bit lighter. So, I can't say for sure 100% that the glycerin doesn't lighten them, but I don't seem to notice an all-of-a-sudden lightening effect, know what I mean?

Plus it may depend on if you'll use it underneath a gel and not alone because it appears you have to use alot of CK if you use it as a styler.
CG-modified since 4/05
2b/3a and 3b on occasion!
Products: The hair aisle in my own cabinets.
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