Because dimethicone leaves a sort of covering on the hair strands, it can also make hair appear shinier. Is it Safe? The FDA approved dimethicone for personal care products, and it is generally considered to be safe to use. The Cosmetic Ingredient Review (CIR) also evaluated the scientific data and concluded that it was safe for use in cosmetics.
Dimethiconol is also great in reducing the effects of the weather elements that cause frizz. Cons Dimethiconol is a non-water-soluble silicone that can buildup easily if not removed regularly clarifying shampoos or cleansers formulated with sulfates.
In hair care products, dimethicone is used to provide smoothness, particularly in conditioners and detanglers, where the ingredient helps smooth hair and provide better comb-through. Because dimethicone leaves a sort of covering on the hair strands, it can also make hair appear shinier.
Phenyl Trimethicone is a derivative of silica, or silcione, and is used in cosmetics and beauty products as an anti-foaming agent, hair conditioning agent, and skin-conditioning agent (Cosmetic Database).