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Kerastase Repairing Damaged Hair

Damaged Hair: The Hidden Perils Of Hard Water

Water - and more specifically the calcium within - can cause damage to your hair. The secret to defending your hair fibers? Decalcification. Discover all there is to know to keep your locks strong, shiny and supple.

Kerastase effects of Hard Water on Hair

Hard water, with its high calcium content, can cause hair breakage especially if it's already damaged, bleached, or processed. Often underestimated for its potential harm, hard water can be a silent assailant to your strands, weakening and dulling them.

The key to saving your hair fibers from this hard water is hair decalcification. In this article, we’ll dive into the science behind why hard water is detrimental to your hair and the practical tips you need - including how to decalcify – in order to protect your hair from hard water.

How Water Can Damage Hair

How Water Can Damage Hair

Water is life, and it plays a crucial role in maintaining our overall well-being. However, when it comes to your hair, the type of water you expose it to can either be a blessing or a curse. Hard water is water that is rich in minerals, predominantly calcium and magnesium.


When we think of hard water, we often think about limescale - that chalky deposit that builds-up around taps and in the depths of your kettle - but when it comes to hair, it’s the calcium that is the real issue. Strange, right? Because when we think of calcium, we often link it to strong, healthy bones and teeth but when it comes to hair, calcium buildup is not your friend - it can, in fact, lead to a range of problems, including hair weakening and breakage.

What Type of Damage Can Calcium Cause to Your Hair?

Now that we know why calcium is good for our bodies but can be bad for our hair when exposed regularly,
here are 3 types of damage that calcium can cause to your hair:

How to Decalcify your Hair and Protect it from Hard Water?

Hair decalcification is the process of removing the damaging calcium buildup from your hair. This procedure is essential for maintaining healthy, lustrous hair, particularly if you live in an area with hard water.
There are several methods for hair decalcification, including specialised shampoos, conditioners, and treatments designed to dissolve and remove excess calcium. Regular use of these products can help restore the natural balance of your hair and prevent further damage.

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To keep your hair looking its best, implement hair decalcification into your routine and use products designed to combat the impact of hard water on your hair. With the right routine and a little extra attention, you can help maintain your hairs strength, even in areas with notoriously hard water.

What Products to Use to Avoid HardWater Damages?

Did you know, damaged hair absorbs 3x more calcium than healthy hair?
That’s where the new hair strengthening range, Première, comes in, as it has been specifically formulated to decalcify your hair fibers using citric acid and glycine – giving your hair a mineral detox.

How Water Can Damage Hair

The Kérastase Première Concentré Décalcifiant Ultra Réparateur boasts the highest percentages of each ingredient: 3% citric acid to eliminate the calcium buildup, neutralizing dullness and stiffness. Added to that is 5% glycine, an amino acid, that penetrates the hair to reconnect broken keratin links (caused by the calcium) to reduce breakage. The dual action repair, both outer and inner repair, can recreate 99%* of your hair’s original strength.


Sounds too good to be true - we know - but it’s not magic, it’s science. Find out how the Kérastase Première Concentré traps and eliminates the excess calcium with this experiment done by Edine Ahbich, Kérastase Scientific Director.

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