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Damaged Hair: Hard Water Takes a Toll On Your Hair

Water, and specifically the calcium in water, can cause damage to your hair. The secret to repairing your hair fibers? Decalcification --removing that calcium. Discover how to keep your locks strong, shiny and healthy.

If your hair is already damaged the calcium in hard water can accumulate, causing peristant damage. Hard water has high levels of calcium that can amplify hair breakage, especially when the hair is already damaged. Hard water can be a silent assailant to your strands causing loss of strength and shine.

Decalcifying doesn’t need to be complicated. In this article, we dive into the science behind why hard water is detrimental to your hair as well as how to easily and effectively decalcify your hair.

How Water Damages Your Hair

Water is good for you, but not always as good for your hair. Hard water is rich in minerals like calcium and magnesium which is great for your body, but can causes build up when it's on your hair.

Think about the limescale in your shower -- that chalky deposit that builds up around the shower head. Now think about how that calcium might effect already damaged hair. When hair is already damaged, calcium collects within the hair fiber and causes weaker, duller hair.

Watch our newest ambassador, Sydney Sweeney, explain the effects of hard water on the hair and how Premiere is your solution.

3 Types of Damage Hard Water Can Cause on your Hair


Calcium weakens the protein structure of your hair, making it more prone to breakage. If your hair is already damaged, your hair is more porous and collects the calcium more easily, exacerbating the problem.


The coating that calcium can form over your hair makes it look dull and lackluster. This layer prevents moisture from entering the hair shaft causing dry and lifeless locks.


Calcium and the protein in your hair react and cause hair to become stiff. Your hair feels coarse and difficult to style, which can lead to even more damage as you style or brush your hair.

How to Decalcify your Hair

Decalcifying your hair is the process of removing calcium buildup from your hair. Removing that build up will result in healthy, strong, shiny hair.

Using specialized treatments, shampoos, and conditioners designed to help dissolve and remove excess calcium is one great way to decalcify. With regular use, these products are designed to help prevent further damage and restore the natural balance of your hair.

Is Premiere Right For You?

Implementing hair decalcification into your routine will keep your hair looking its best. With the right routine, using products that are designed to combat the impact of hair water on your hair will keep your hair strong and healthy.

Learn More About Our Dual Action Repair Haircare

Our new dual action haircare, Premiere, has been specifically formulated to decalcify your hair fibers using citric acid and glycine. These two ingredients give your hair a mineral detox, focused on removing calcium buildup from your hair.

The new Première Pre-Shampoo Treatment has the highest percentages of citric acid and glycine. The 3% citric acid eliminates calcium build up and neutralizes dullness and stiffness. The 5% glycine is an amino acid that penetrates the hair and reconnects broken links between keratin chains, which reduces hair breakage. This duo is your key to dual action repair. It targets both the inner and the outer layers of your hair and restores up to 99% of your hair's original strength*. * with continuous use of the full system

Your At Home Decalcification Routine

The key to the Premiere range is the power of layering. Fisrt, apply the Premiere Pre-Shampoo Treatment to damp hair. Then layer on the Premiere Shampoo, this action of layering helps to decalcifying the hair effectively. The Pre-Shampoo Treatment's powerful active ingredients are able to penetrate the different layers of your hair for optimal decalcification and repair.


Apply the Kerastase Pre-Shampoo Treatment, Première Concentré Décalcifiant Ultra Réparateur on damp hair. Massage in and let sit for 5 minutes, do not rinse.

With 3% citric acid and 5% glycine, it decalcifies your hair reducing stiffness, boosting shine, recreating 99%* of hair’s original strength and reducing breakage by 93%**.
*with continuous use of the full system
**vs. nonconditioning shampoo


Apply the Kérastase Première Bain Décalcifiant Réparateur directly on top of the Pre-Shampoo Treatment.

You feel it gently cleanse away calcium overload and neutralize dullness and breakage. It repairs persistent damage, reversing stiffness and dullness for 73% shinier hair**, and 2x smoother hair***. Hair is 93% stronger***.
**vs. unwashed hair
** vs. non conditioning shampoo


After rinsing the Pre-Shampoo Treatment and the Bain out of your hair, apply the Kérastase Première Fondant Fluidité Réparateur, or the Masque Filler Réparateur depending on your hair type.

Leave the Fondant on for 3-5 minutes for best results and the Masque on for 5-10 minutes, allowing the hydration to sink into the hair fibers.


The Kérastase Première Sérum Filler Fondamental is your heat styling hero. This serum treats and protect hair from heat tools up to 450 degrees.

Huile Gloss Réparatrice is your finishing touch. This nourishing oil seals split ends and boosts shine. Touch up your hair after heat styling and tame flyaways with this hydrating oil.

Ask your stylist about our salon-exclusive decalcifying and repairing treatment. This professional decalcification treatment will work wonders on damaged hair and begin your decalcification routine. This service, reverses persistent stiffness, seal in shine, get stronger, and shinier hair with your trusted stylist.

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