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What does shampoo do? Discover how shampoo works

Check out our step-by-step guide to how your shampoo cleanses and protects your hair to keep it clean and looking beautiful. 


Your skin produces the natural oil, sebum, which protects your hair and hair follicles.While it’s really beneficial, it can also build up and leave your hair looking greasy.

Dust, pollen and dirt get attached to the oil too, contributing to the dull, oily look. Sebum is an oil, which means it’s hydrophobic –and if you’ve ever tried to mix oil and water, you know it just won’t work.

So, when it comes to washing it off, water alone won’t do the job.

Read more on what is sebum

How Shampoo Works


This 3-step process is what the very best shampoos do and we’ve brought it to our entire collection with our new tri-action formula.

The upgrade takes its inspiration from leading skin care products and cares for your scalp in 3 steps:

  1. cleans – with gentle cleansing agents that wash away dandruff flakes, grease and oil to leave your hair noticeably cleaner

  2. protects – the new formula contains micro-minerals which are left behind after you wash your hair to protect against dandruff damage so your hair can grow from a healthier foundation

  3. moisturizes – it instantly delivers extra conditioning to leave your hair feeling soft and smooth while the micro-minerals help to repair the scalp and lock in more moisture


  1. Shampoo contains molecules called surfactants. These emulsify the sebum, allowing it to mix with water

  2. When you rinse, the water takes the emulsion with it, including all the dirt and grease

The more grease there is attached to the surfactant molecules, the less the shampoo will lather.

That’s why the first time you wash really dirty hair, you might not get a huge lather – but repeat it after rinsing and you’ll notice your lather is much bigger the second time around!


Some shampoos are specifically designed with extra ingredients – sometimes to give you a different sensation in the shower and other times to give you additional hair benefits:

  • itchy scalp shampoos often contain cooling agents like mint or eucalyptus.

  • different scents are added like Apple Fresh or Citrus for great-smelling hair.

  • anti-dandruff shampoos like our Classic Clean Shampoo contain agents like zinc pyrithione to fight dandruff and keep it from coming back.


Some shampoos are formulated with moisturizers to condition and restore a protective coating on the hair.

Our Smooth and Silky 2-in-1 provides your hair with a deep cleanse while keeping it moisturized and virtually frizz-free, leaving your hair smooth and full. Our formula is pH balanced, and it’s gentle enough to use on your hair every day.

More hair care tips and tricks More tips and advice from the experts: