what causes keratin buildup
Keratosis pilaris results from the buildup of keratin â a hard protein that protects skin from harmful substances and infection. The keratin forms a scaly plug that blocks the opening of the hair follicle. Usually many plugs form, causing patches of rough, bumpy skin. No one knows exactly why keratin builds up. But it may occur in association with genetic diseases or with other skin conditions, such as atopic dermatitis.