Why Does Chlorine Make Hair Curly? Curls After Swimming: Explained!

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Many of us step out of the pool and towel-dry our hair a bit, only to find that the chemicals in the pool have made our locks surprisingly curly! What’s the deal with that?

Why does chlorine make hair curly? It has to do with the pH level of the water in the pool.

We’ll explain it in detail below!.


How Does Chlorine From a Pool Affect Your Hair?

The chlorine in water interacts with the hair’s natural oils and reacts with protein molecules in the hair, which causes them to bind together and lose their shape. 

This process makes hair prone to breakage and forms a curly hair texture.

Pool chlorine can also cause hair color to fade, dry out, turn a greenish tint, and can lead to breakage and split ends. All of these factors make chlorine a harmful substance for hair.

Unfortunately, some people use chlorine to bleach their hair and make it lighter in color. It is a bad choice as it has drastic effects on the hair. 

Why Does Chlorine Make Your Hair Curly?

The answer to this question has to do with the pH level of the water. Chlorine is a chemical that is found in tap water, but it is at much higher levels in pool. When it mixes with water, it creates a chemical reaction and produces a substance called hypochlorous acid.

Hypochlorous acid can also be found in other things like bleach, soaps, and detergents.

The chlorine reacts with the protein called keratin, which makes up your hair. The reaction causes the keratin to coagulate or clump together. 

The chlorine reacts with the protein called keratin, which makes up your hair. The reaction causes the keratin to coagulate or clump together. 

Keep in mind the shape of your hair depends on the shape of the molecule that builds up your hair. The keratin molecules are like long ropes wrapped around each other in countless numbers forming the shape of a twisted rope. 

However, the shape gets disrupted when the chlorine reacts with these keratin molecules.

This entire process makes the hair strands curl up and change their texture. Hence: curly hair after you step out of the pool!

This entire process makes the hair strands curl up and change their texture. Hence: curly hair after you step out of the pool!

How Does Chlorine in Shampoo Work on Your Hair? 

Chlorine is also found in some household items, such as shampoo. However, a new study found that chlorine in the shampoo can make the hair dry and brittle, eventually leading to breakage or a change in texture. 

It is because chlorine reacts with the natural oils on your scalp to produce chloroform, which strips your hair of its natural oils.

The study also discovered that the more often you use shampoo containing chlorine, the more damaged hair becomes, changing into a frizzy and curly texture

Prevent Hair Damage from Chlorine 

There are a few easy ways to prevent hair damage from pool chlorine.

1. Filters

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Many people have started using filters on their showers  or installing a whole house water filter to avoid this problem.

The first step to reducing chlorine damage is determining your hair type. The most sensitive hair types are curly, chemically treated, and color-treated.

These types of hair should be washed with water that has been filtered or softened before using it.

2. Leave-in Conditioner

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If you do not have access to these resources, you can do some other things to minimize the damage from chlorine. Use a leave-in conditioner or hair mask before getting into the chlorinated water.

You can also use a moisturizing shampoo and conditioner on your hair after washing it with chlorinated water to protect your hair strands from drying out and breaking off.

3. Swim Shampoo

TRISWIM Chlorine Removal Swimmers Shampoo Moisturizing Repairing Hair, 8.5 fl.oz.
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It is better to choose a swim shampoo  to protect your hair from regular chlorine exposure.

You should also avoid washing your hair more than once a day and make sure that you rinse thoroughly after each wash cycle.

4. A Swim Cap

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It definitely doesn’t improve your look, but a swim cap is an excellent option for those who want to protect their hair from the harmful effects of chlorine. If you’re swimming regularly, it’s a good idea to pick one up.

5. Careful Cleaning

Chlorine does not rinse out of your natural hair easily if it is left in your hair for more than 24 hours. Instead, it enters the hair cuticle while causing potential damage to the inner layers of the hair strands. Therefore, cleaning your hair instantly after every swim is very important. 


You likely already know by now how chlorine turns your hair texture into curls and dries out your hair. The curls can look good for a little while, but they are a sign of hair damage. Hair with a curly texture is naturally drier than straight or wavy hair.

Therefore, chlorine can worsen your curls.

Written by Kayla Young

Kayla is the founder of LuxeLuminous. She has worked professionally in the tanning industry for years. She has been interested in esthetics since childhood, and has tried every hair, skin, and makeup product ever produced (more or less).