Nioxins Cleanser Shampoo System 1 for natural hair with light thinning is the first step of a three part Nioxin regimen, specially formulated to strengthen the hair to prevent breakage and amplify hair texture. It prepares the hair and scalp for a complete hair thickening treatment with Nioxins three part System 1. This professional derma-purifying Cleanser Shampoo removes dirt, excessive oil and other environmental residues from the scalp and hair.