Which ingredient is commonly added to hair products for conditioning?

Silicone is frequently added to hair products for conditioning due to its ability to create a protective barrier around the hair strands. This barrier helps to lock in moisture, reduce frizz, and enhance shine, making the hair appear smoother and more manageable. Silicones are also known for their excellent spreadability and are effective at filling in gaps in the hair's cuticle layer, which improves the overall texture and feel of hair when styled.

In contrast, ammonia is typically found in hair color formulations and is not a conditioning agent; it is used for its ability to open the hair cuticle to allow for color penetration. Biotin, while beneficial for hair health as a supplement, does not have the same immediate conditioning properties as silicone when applied topically in hair products. Ethyl alcohol can be a drying agent in products, as it can strip natural oils from the hair, making it less suitable for conditioning purposes. Therefore, silicone stands out as the primary ingredient that effectively conditions and enhances the appearance of hair.