Nioxin Scalp + Hair Thickening Shampoo (System 2)

All hair and skin types.

Almost always the first ingredient listed in water-based products.

Oily scalps, heavy product users and people who like a strong cleanse.

May feel too cleansing for some dry, curly, colour-treated or sensitive hair types. This depends on the full formula and your hair needs.

Oily scalps and routines that need a strong, clarifying wash.

Can be more cleansing than gentler surfactants. Many people use it happily, while others prefer milder options for everyday washing.

Most hair types, including those wanting a gentler wash.

Often paired with other surfactants to make a formula feel milder.

All products that need a preservative system.

Often paired with other preservatives for broad protection.

Most hair types as part of a balanced formula.

Usually present in small amounts to balance the formula.

Those interested in how a product’s texture and lather are achieved.

It is a simple mineral salt that helps create a familiar shampoo feel and can influence how a cleanser spreads through the hair.

Those in hard-water areas who want shampoos and conditioners to rinse more cleanly.

Chelating agents can support formula consistency and help prevent minerals from depositing on the hair or interfering with product texture. They are widely used in many rinse-off and leave-in formulations.

Most hair types as part of a moisturising formula.

A widely used humectant and carrier ingredient.

Dry or dehydrated hair, and many curl and moisture routines.

A very common, well-tolerated humectant used across countless products.

Those interested in how product pH affects scalp comfort or hair cuticle behaviour.

It is used in very small amounts to bring a formula to the desired pH range. Once adjusted, it does not act as a strong alkaline agent in the finished product.

A fragrance component that must be listed separately on labels because a minority of people can be sensitive to it. Its presence is normal, required disclosure and is not a quality signal.

Most hair types, especially dry or dull hair.

A versatile, well-tolerated conditioning ingredient.

Those looking for added conditioning support or antioxidant benefits in their haircare.

It is commonly used because it is more stable than pure vitamin E while still offering similar benefits. It appears in many leave-in and rinse-off formulations.

All products that need protecting from spoilage.

A very common, well-studied preservative used at low levels.

Anyone who uses water-based products that benefit from reliable preservation.

It is commonly used alongside other preservation systems to maintain product freshness and extend shelf life. It is generally well tolerated in rinse-off and leave-in products.