Why Are Shampoos Acidic?

By Audrey Sivasothy

Quite a bit of science goes into formulating hair products. Considerations for product pH, smell, consistency and overall effectiveness are common manufacturer concerns. Shampoos are formulated at an acidic pH to help the hair maintain its natural, acidic mantle.

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Shampoo ingredients are acidic.

What is Shampoo?

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Shampoo is formulated to cleanse the hair.

Shampoo is an acidic product made up of water, detergents, silicones, thickeners and proteins. It is formulated to cleanse the hair.

Types of Shampoos

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Many types of shampoos are on the market.

There are several types of shampoos including: chelating shampoos for mineral removal, clarifying shampoos for product buildup removal and moisturizing shampoos for restoring the hair's elasticity. Other shampoos are formulated to do a variety of things such as volumize hair strands, preserve hair color and thicken the hair.

Why is Shampoo Acidic?

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Shampoos improve the appearance of hair.

Shampoos are acidic to preserve the hair's own natural acidity. Acidic products help keep the hair's cuticle layers oriented downward, improving shine and hair appearance.

Acidic Ingredients

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Citric acid is common in shampoos.

In order to maintain pH levels between 4 an 6, many shampoos contain acidic ingredients like citric acid or sodium citrate.

Fun Fact

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Shampoos are mostly water.

Shampoos are about 80 percent water.