How Chlorine Affects Hair — The Science
What Does Chlorine Do to Hair?
- Strips natural oils: Chlorine in the water removes the oil layer that keeps your hair smooth.
- Dries hair out: Hair exposed to chlorine becomes dry, rough, and brittle.
- Raises hair porosity: Gaps form in your hair’s surface, leading to more breakage and easy color loss for color-treated hair.
- Discolors hair: Especially in light or colored hair, excessive chlorine exposure can cause a greenish tint.
- Chlorine residue: If left on your hair, chlorine dries out both your hair and scalp, leading to irritation or dandruff.
- Indirect effects: Chlorine in tap water or drinking water can cause cumulative dryness and skin irritation over time.
Does tap water have chlorine?
Infographic: Anatomy of a Hair Strand Pre- and Post-Chlorine Exposure
Hair Feature
|
Before Chlorine Exposure
|
After Chlorine Exposure
|
Surface Cuticle
|
Tight, smooth
|
Rough, lifted, porous
|
Moisture/Oil Content
|
Balanced, healthy
|
Stripped, dry
|
Color (in color-treated hair)
|
Vibrant, even
|
Faded, sometimes greenish
|
Strength
|
Flexible, less breakage
|
Weak, prone to split ends
|
How to Protect Hair from Chlorine: Step-by-Step Routine
Pre-Swim: Essential Protective Steps
1. Rinse your hair with clean, non-chlorinated water
Wetting your hair before swimming makes it absorb less chlorinated pool water. Just like a sponge that’s already wet can’t soak up much more water, your hair, when saturated with fresh water, will take in less chlorine.
2. Apply a protective barrier: Natural oils or leave-in hair conditioner
Oils and conditioners create a thin shield on each strand, making it harder for chlorine in the water to reach your hair. Should you oil your hair before swimming? This is one of the best steps to lock in moisture and form a barrier.
- Natural Oils vs. Silicone-Based Conditioners: Which is Better?
Product Type
|
Protection Level
|
Pros
|
Cons
|
Best For
|
Coconut oil
|
High
|
Deep penetration, natural, affordable
|
May be heavy for fine hair
|
Thick, curly, dry
|
Olive oil
|
Medium-High
|
Easily available, hydrates
|
Can look greasy, heavy
|
Thick/curly
|
Jojoba oil
|
Medium
|
Lightweight, less greasy
|
Slightly less protection than coconut
|
Fine/straight
|
Silicone leave-in
|
High
|
Smooth finish, easy to style
|
May cause buildup over time
|
All types
|
Cream conditioners
|
Medium
|
Moisturizes, detangles
|
May rinse out quickly in water
|
All types
|
3. Wear a swim cap

- For long or thick hair: Tuck hair into a loose bun or braid before putting on the cap to prevent tangling.
- For curly or textured hair: Use some oil or leave-in conditioner first, then choose a large-size silicone cap that won’t pull or flatten your curls.
Pre-Swim Routine Builder: Printable Checklist Example

Immediate After-Swim Care
1. Rinse your hair thoroughly with clean water (as soon as possible)
Before every swim, saturate your hair with fresh water to reduce chlorine absorption. Think of it like a sponge—when it’s already wet, it can’t soak up much more. Similarly, fully wet hair is less likely to absorb chlorinated pool water. Dermatologists and swim coaches alike recommend this simple step as one of the most effective defenses against chemical damage.
2. Use a clarifying or chelating shampoo
These shampoos are designed to remove chlorine, not just surface dirt, and are especially useful for regular swimmers. They help prevent green-tinted hair, product buildup, and excessive dryness caused by pool chemicals.
However, because they are more intensive than regular shampoos, they should be used sparingly to avoid over-drying your hair and scalp.
Use clarifying shampoo up to 1–2 times per week, depending on how often you swim.
Chelating shampoos—the most powerful—should be used no more than once a week, unless recommended by a professional, as overuse can strip essential oils and cause brittleness.
For color-treated or sensitive hair, opt for a gentle, sulfate-free clarifier to reduce irritation and maintain color vibrancy.
Shampoo Type | Removes Chlorine? | Pros | Cons | When to Use |
---|---|---|---|---|
Regular shampoo | × | Gentle, everyday use | Won’t remove chlorine fully | After casual swim |
Clarifying shampoo | √ | Removes chlorine/build-up | Can be drying | 1–2x/week for swimmers |
Chelating shampoo | √√ | Removes minerals, metals | Strongest (may be harsh) | Occasional deep cleanse |
3. Apply a hydrating conditioner or deep-conditioning mask This final step restores moisture after chlorine exposure.
- DIY: Make a mask with plain yogurt and honey for protein and hydration. While these DIY masks are great for weekly nourishment, they should complement a swimmer’s core routine (such as leave-in repair sprays or deep conditioners) for optimal protection and recovery.
- Store-bought: Select a deep conditioner rich in natural oils and proteins.
- Let your hair air dry, or use a microfiber towel.
Post-Swim Recovery for Frequent Swimmers

Signs of Chronic Chlorine Exposure:
- Hair looks straw-like and feels crunchy
- Color fade, green tint (especially in light hair)
- More split ends and breakage than normal
- Itchy, flaky scalp
Weekly Routine for Regular Swimmers:
- Deep-conditioning mask or repair serum once per week
- Use leave-in sprays that help repair and shield against chlorine
- Trim your ends every 6-8 weeks to control breakage

Tailored Advice by Hair Type
Hair Type
|
What to Use
|
Avoid
|
Color-treated
|
Color-safe, extra-moisturizers
|
Harsh clarifiers, frequent use
|
Curly/Textured
|
Sulfate-free, thick oils
|
Strong clarifying shampoos
|
Fine/Thinning
|
Lightweight oils, protein treatments
|
Heavy oils/conditioners
|
How to Minimize Chlorine Exposure Beyond the Pool
- Use filtered water for final rinses: If your water system contains much chlorine, rinse your hair with filtered or distilled water.
- Install a shower filter: These filters can remove chlorine and other chemicals from tap water, improving hair and skin health.
- Consider a Reverse Osmosis (RO) filter: For your whole home’s drinking and washing water, an RO filter reduces total chlorine exposure.

Expert Advice & Case Studies
Insights from Dermatologists and Pro Swimmers
Real-Life Case Example
Infographic: Myths vs. Facts About Hair and Chlorine
Myth
|
Fact
|
Everyone gets green hair from chlorine
|
Only light or damaged hair, often from copper in water
|
Swim caps alone prevent all chlorine contact
|
Even the best swim caps can let some water in—especially around the edges.
|
Chlorine in tap water is too mild to matter
|
Daily use can still dry hair over time
|
Oils harm hair or scalp
|
Natural oils protect, unless hair is very fine
|
Only pool water affects hair
|
Chlorine in tap or well water can also dry hair
|
Conclusion
FAQs
1. How can I protect my hair from chlorine damage?
2. Does wetting your hair protect it from chlorine?
3. Should I oil my hair before swimming?
4. Will swimming once a week damage my hair?
5. What does chlorine damage look like?
6. Does chlorine in water affect your hair?
7. Can drinking tap water affect your hair?
8. Can I swim without a swim cap and still protect my hair?