Ever wonder why certain hair products—like shampoos and conditioners, leave-ins, or hair masks—do wonders for your friends with similar curl patterns, but leave your hair in a frizzy heap? Or why products that seem to do wonders for every user on TikTok render your 'do greasy or cause unprecedented breakage? While many have been led to believe that hair thickness and type are the only characteristics to bear in mind when shopping for haircare, there is, in fact, another important factor that's often overlooked: Hair porosity, of the ability of hair to retain and absorb moisture. Low porosity hair struggles to maintain moisture, while high porosity hair absorbs it like a sponge.
"To have high-porosity hair means that the cuticle scales are raised due to over processing, damaged by chemical services like color, perms, relaxers, or rough manipulation from heat and other hair care tools," Alicia Bailey, a licensed master cosmetologist and the CEO & Global Hair Education Director of Iman Yvonne Beauty, explains. "The hair will absorb color, hair products, and water quickly, but will have trouble holding onto the color or moisture due to the cuticle layer being open. High porosity hair appears frizzy, feels dry, is usually fragile and will break fairly easily."
