Grandiose hair color transformations have become the norm in today's society. All over the world, people are using bleach to go from super dark brown to icy platinum blonde and every color in-between.
While experimenting with bleach is a lot of fun, many find themselves wondering whether they're doing permanent damage to their hair in the process. In this article, we'll tell you whether bleaching your hair damages it forever and what you can do to preserve your hair as you try out the latest color trends.
Does Bleaching Your Hair Damage It Forever?
Without a doubt, bleach can cause damage to your natural hair, and when it does, it is permanent. There's no way to magically restore your damaged hair to its previous state.
Once your hair is burnt beyond recognition because you used 50 volume developer or left the bleach on too long, it will never be the same again.
You may be able to slightly improve your hair's condition, but this is not guaranteed. To understand why bleach causes permanent damage, we'll jump into the composition of bleach. Read on.
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How Does Bleach Damage Hair?
Hair bleach is an alkaline persulfate powder, usually ammonium or potassium persulfate, mixed with hydrogen peroxide at up to 12 percent. Together they lift your cuticle and break down the melanin granules that hold your natural color.
What Does Bleach Remove From Your Hair?
Your natural hair color comes from melanin granules in the cortex, the thick middle layer of each hair strand. Keratin, the protein your hair is made from, has no color of its own. Bleach lightens your hair by breaking down those melanin granules, and you can't reverse that change once you've bleached a strand.
Once you mix the bleach, its alkalinity lifts the cuticle so the peroxide can reach the cortex. Peroxide oxidizes melanin, which is why brown hair passes through red and orange shades before reaching yellow.
That same chemical reaction can also damage your keratin.
It breaks some disulfide bonds, the sulfur links that help give your curls strength, shape, and stretch.
In 2024, researchers examined hair bleached three times under an electron microscope. The untreated hair had relatively clean, intact cuticle scales. The excessively bleached hair looked very different. Its cuticle scales were torn, lifted, and sometimes completely missing.
Where the cuticle had peeled away, the exposed cortex had developed long cracks.
Inside the cortex, dissolved melanin granules had left small holes behind.
One part of the hair held up better. The macrofibrils, the bundles of keratin running through the cortex, kept their overall shape. That doesn't mean the hair was healthy, but it does mean some of its core structure remained even after severe bleaching.
Sorted by what actually comes back
What bleach changes, and what you can actually get back
Bleach changes several parts of your hair, and they don’t all recover in the same way. The study above examined excessively bleached hair, so your damage may be milder. Find the part you’re worried about below to see what can improve and what can’t be restored.
| Does it come back? | Part of your hair | What bleach does to it | What actually helps |
|---|---|---|---|
| No | Your natural color | Bleach breaks down the melanin granules that hold your natural color. With excessive bleaching, those granules can dissolve and leave holes inside the cortex. | Nothing puts your natural melanin back into a bleached strand. Toner and dye can add artificial pigment, but only new growth comes in with your natural color. |
| No | Lost cuticle scales | Bleach lifts and weakens the overlapping scales on the outside of your hair. With severe damage, some scales can tear or peel away completely. | Conditioner, leave-ins, and sealing products can smooth and lubricate what remains, but they can’t grow a missing cuticle scale back. Trimming removes the worst damage over time. |
| Partly | Your disulfide bonds | Bleach oxidizes some of the sulfur bonds that help hold your hair’s keratin in shape. | Bond-building treatments may improve strength and reduce breakage, but they won’t return your hair to its virgin condition. |
| Partly | Strength and stretch | Damaged bonds, protein loss, and weakened cuticle scales make your hair easier to stretch, split, and snap. | Condition regularly, handle your curls gently, and limit heat and tight styles. A protein treatment may provide temporary support if your hair responds well to it. |
| Manage it | Porosity | Damage to the cuticle allows your hair to take in and lose water more easily. That’s why bleached curls may get wet quickly and still feel dry again soon afterward. | Apply a leave-in to damp hair and follow with a sealing product. You’re slowing moisture loss rather than permanently closing the damaged areas. |
| It survived in the study | The core of your strand | The macrofibrils kept their overall shape even in the excessively bleached hair examined by researchers. | Protect the structure that remains with conditioning, gentle handling, less heat, and regular trims. An intact core doesn’t mean the surrounding hair is undamaged. |
Once bleach removes melanin or causes a cuticle scale to break away, your body can’t replace it inside that strand. How much damage you experience depends on the bleach strength, how long it processes, your hair’s condition, and whether you bleach it repeatedly. From there, the goal is to protect your length and gradually trim away the most damaged ends. Sources: Applied Microscopy, 2024: effects of excessive bleaching on hair.
You're left with a weakened, albeit lighter, version of your hair. The longer you leave the bleach in, or the stronger the developer you use, the lighter and weaker your hair color becomes.
The bleaching process disrupts the natural elasticity and porosity of the hair. It also ruins your hair texture making it more brittle and dry. Though you can treat your bleach-related hair problems, the effects will be permanent.
How To Minimize Permanent Damage from Bleaching Hair?
Damage from bleaching is inevitable, but there are several ways to minimize it. Check out the list below for some helpful damage prevention tips:
See a Professional Hairstylist
Everyone knows that professional bleaching sessions are expensive but asking a hairstylist for help is great for people with curly or compromised hair.
Professional colorists examine your hair texture and preferences and use the gentlest possible bleach mixture on your hair. For this reason, going the professional route can minimize permanent damage from bleach.
Use a Good Quality Bleach
Using a pre-packaged bleach kit is rarely a good idea. The bleach in these kits may have abnormally high concentrations of chemicals, which increases your risk of permanent damage.
Since everyone has a different hair type, it's better to pick out customized bleaching products versus pre-formulated ones. Some of the best professional bleach brands include Wella, Clairol Professional, and Schwarzkopf.
Use a Low-volume Developer
When it comes to hair bleaching, you should always start with a low-volume developer, especially if it's your first time bleaching your own hair. Using a high-volume developer (30 volume and over) will likely fry your strands.
10 and 20 volume developers are much gentler on the hair and are less likely to leave you with visible damage.
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Try a Test Patch
It's better to stay on the safe side rather than regretting everything later. So, take your chosen bleach and mix it with your developer, depending on how much lift you want, and then apply it to the hair behind your ear.
Follow the instructions on the box and leave it on for the amount of time indicated on the package instructions. If you see no signs of damage, feel free to use it on the rest of your hair.
Don't Bleach Recently Washed Hair
Don't wash your hair right before bleaching, or it can lead to excessive scalp irritation, which can damage your hair follicles. Naturally, our scalp produces an adequate amount of necessary oils (sebum) that moisturize our scalp and hair.
If you wash your hair before bleaching, your scalp and hair will have nothing to protect it from the harsh chemicals in the bleach. If necessary, wash your hair 48 hours before bleach day.
Don't Overprocess
Many bleach-related hair disasters can be prevented by setting a timer and rinsing the bleach out on time. Though bleach begins to damage your hair immediately after you apply it, the less time it sits on your hair, the better.
So, do yourself a huge favor and set your timer immediately after you're done applying the bleach. Your hair will thank you.
Can You Repair Bleach Damaged Hair?
Can Bleached Hair Be Healthy Again?
Bleached hair can look, feel, and behave much better with the right care, but the strands themselves don't heal. Your skin can repair itself because it's living tissue. Your hair isn't living tissue, so your body can't replace natural pigment or cuticle scales that bleach has already removed.
The hair you bleached will carry some degree of damage until you cut it off. From here, everything is about managing that damage: keep it conditioned, reduce friction, limit heat, and handle it gently to reduce breakage.
However, the new hair growing from your scalp is free of bleach damage, as long as your scalp is healthy and you don't overlap bleach onto that growth later. Regular trims gradually remove the oldest, most damaged ends while you protect the healthier length coming in.
You can't restore your hair to its original condition (e.g., virgin hair), but there are ways to considerably improve your hair's health. With a few hair care routine changes, you can make your curls shinier, stronger, and more elastic after a bad bleaching session. Read about your options below:
Hydrating and Sealing
Almond, argan, coconut, and olive oils all help hydrate your hair. Coconut oil has the most evidence behind it. Lauric acid, its main fatty acid, is a small straight molecule with an affinity for hair protein, and a study in the Journal of Cosmetic Science found it cut protein loss in both damaged and undamaged hair where sunflower and mineral oils did nothing. The others can get into your strand too, so they're still worth using on bleached hair. A study in the Journal of Cosmetic Dermatology found argan oil also cut protein loss when it was put on before a chemical that damages hair the way bleach does.
Sealing oils, such as jojoba oil and Jamaican black castor oil, seal in the hair's moisture for lasting hydration. In addition, you can restore your hair's shine and prevent further breakage with pre-poos and hot oil treatments.
Avoid Heat and Sun Damage
After bleaching, your hair will be more vulnerable to heat, so we recommend using heat protectants and other hair products that contain SPF protection to protect against UV rays. Also, if you can avoid heat styling for a while, you'll notice a real difference in your hair.
Use Deep Conditioning Treatments and DIY Hair Masks
Deep conditioners are extremely popular in the natural hair community because of the vast array of benefits they bring to damaged hair.
With a simple internet search, you can find protein-based deep conditioners, moisturizing deep conditioners, anti-breakage deep conditioners, and much more. Some ladies also use a pre-shampoo conditioning treatment (click here to learn more).
Masks containing honey, bentonite clay, egg white, rice water, and similar ingredients are worth trying. They condition your hair and make it easier to handle, which is a real benefit, though none of them rebuilds what the bleach broke.
Avoid Tight Styles
Your hair will be noticeably weak after bleach damage, so it's crucial to opt for gentle, loose hairstyles. Stay away from tight braids, top knots, low buns, and any other styles that require you to slick your hair back. These styles will often leave your hair damaged if you're not extremely careful.
Avoid Chlorine
Do not swim in pool water for the first three weeks after bleaching your hair. Pool water contains high amounts of chlorine, which can further weaken your hair's protein bonds.
Green hair is a real risk for you now, but chlorine isn't what causes it. Dermatologists call it chlorotrichosis, and it's copper that does it, picked up from pool water or from copper household plumbing. It binds to light-colored, already-damaged hair, which is why bleached blondes get it and nobody else does. A swim cap helps, and so does rinsing with clean water straight after you get out. If your hair has already turned, a chelating shampoo, meaning one that binds metal and lifts it off, is what clears it; one case cleared over about eight weeks that way.
Rinse Hair With Cold Water
It's better not to wash your freshly bleached hair with steaming hot water. Hot water strips more of the oil your scalp puts out, and on bleached hair there's less holding that moisture in to begin with.
Excessive hair dryness, especially after bleaching your hair, puts you at an increased risk of breakage. Instead, use cold water when washing your hair to lock in some much-needed moisture.
Use a Leave-in Conditioner
Leave-in conditioners help nourish hair on a daily basis. They are usually more lightweight than regular rinse-out conditioners, making them ideal for styling.
You can buy a leave-in at your nearest beauty supply store but be sure to check the ingredients - you need one that has moisturizing ingredients like aloe vera, olive oil, and honey.
Frequently Asked Questions
Does bleaching your hair make it thinner?
Bleaching can make each strand weaker and may eventually make your hair look thinner overall. Bleach breaks down melanin, oxidizes hair proteins, and can damage the cuticle. With repeated or excessive bleaching, that damage makes your strands more likely to split and snap.
Bleach doesn't automatically make the new hair growing from your follicles thinner. The loss of fullness usually happens along the bleached length as weakened strands break off.
Does bleach damage your hair more than dye?
Yes, usually, especially when you're lifting your hair several levels. However, permanent hair dye can also damage your hair because it uses an alkaline formula and developer to change your color. But bleach is designed to remove much more of your natural pigment, so it generally causes more damage.
Deposit-only colors, including most semi-permanent dyes, are gentler because they add pigment without significantly lightening your hair. The amount of damage still depends on the formula, developer strength, processing time, and condition of your hair before you start.
Does bleaching permanently damage your scalp?
Not usually, but it can if the bleach causes a serious chemical burn. Your scalp is living skin, so that mild irritation can heal. A deep burn, however, may scar your skin and damage the follicles underneath it, potentially leading to permanent hair loss in that area.
A burning sensation during processing is your signal to rinse the bleach out immediately. If your scalp blisters, swells, weeps, develops open sores, or remains painful after rinsing, contact a healthcare professional.
Can you bleach hair that is already bleached or damaged?
Hair that has already been bleached can sometimes be lightened again if it's still strong enough, but applying bleach over the same length increases your risk of severe breakage. Hair that is already gummy, brittle, splitting, or snapping shouldn't be bleached again.
When touching up your roots, apply bleach only to the new growth and keep it off the hair you previously lightened. If you're unsure whether your curls can handle another bleaching session, do a strand test or see an experienced colorist before moving forward.
Related Articles
- How to Slightly Darken Bleached Hair at Home
- Stages of Bleach on Black Hair
- How to Bleach Black Hair at Home Without Damage
- How to Bleach Dreads Without Damage
So, there you have it - bleaching your hair can cause permanent damage that is unrecoverable in the vast majority of cases. Those hair-altering bleaching agents are to blame.
However, with proper care and remedies, you can minimize bleach damage and improve the quality of your bleached hair over time. We wish you the best with your hair!
