17 Facts About Chemically Straightening Your Hair (2023)

17 Facts About Chemically Straightening Your Hair (1)

From Cosmopolitan

If your hair is uber thick, curly, or frizzy, or you're just not that into your texture, you might have considered getting your hair chemically straightened. But the pricey salon services have recently come under fire for causing some super-scary side effects, with hair damage being the least of it. Here's what you need to know before putting your hair and health at risk:

1. Chemical straighteners work by changing the structure of your hair. Each hair is made up of grouped chains of keratin, a naturally occurring protein. Chemical treatments affect the way these chains are held together to effectively de-coil each strand.

There are several different types of in-salon chemical straightening and smoothing treatments, with Japanese and Brazilian being the most common ones. Both processes involve coating each strand with a strong chemical, then warming it up to activate the formula.

The Japanese straight perm is a permanent straightening solution that only requires touch-ups as your roots grow in about every six months. It can cost between $150 and $800 per treatment, depending on the salon. Because it involves the strongest chemicals, it poses the greatest risks in terms of damaging your hair.

Then there are keratin treatments (aka Brazilian hair straightening or smoothing). The semi-permanent technique can last between three and five months, and puts you out about $150 to $300 per treatment. It won't give you pin-straight hair, but it does significantly reduce curls, frizz, and styling time with results that stand up to humidity, according to Natalija O’Toole, a stylist in New York City.

2. The process takes two to three hours - but you won't walk out of the salon with your best blowout ever. At the salon, the stylist will shampoo your hair, then apply the chemicals to dry or damp hair section by section. Different formulas require different amounts of time for processing, so you sit tight for a bit. Then your stylist blow-dries your hair and flat-irons it at a very high heat. Afterward, your hair will be straight, shiny, and silky, but flat and filled with product that can make it somewhat greasy and smell like strongly like chemicals, according to O’Toole.

3. After chemical straightening, you can't wash your hour for at least 12 hours after treatment. This drying time, which can last up to several days depending on your stylist's recommendation, allows the product to set in.

4. Many chemical smoothing treatments contain high levels of toxic ingredients. Turns out formaldehyde, the chemical used to preserve cadavers, also helps many keratin chemical hair straighteners work their magic. Unfortunately, even one-time exposure to the high levels of this toxin can trigger horrible symptoms, according to Tina Sigurdson, Environmental Working Group (EWG) assistant general counsel and co-author of several studies on hair straightening treatments.

"In general, every client and stylist [exposed to keratin chemicals] complains of burning eyes, difficulty breathing, and burning sensations," estimates Kelly Merriman, a stylist from Joliet, Ind. Customers have also complained of throat and mouth ulcers, dizziness, headaches, flu-like symptoms like vomiting, eye damage, loss of taste and smell, and fatigue, according to Sigurdson. And because exposure is cumulative, salon workers are extra likely to suffer from severe symptoms.

While the chemicals aren't supposed to touch anything but the hairs themselves, accidental skin contact can cause blisters or rashing on the scalp, face, and neck.

But that's just in the short term. Formaldehyde is also a known carcinogen, which means it's proven to cause cancer in humans, with higher levels and prolonged exposure posing greater risks.

5. "Formaldehyde-free" hair chemicals can still contain or release the ingredient.

Chemical hair straightening products containing formaldehyde are already outlawed in certain U.S. states (California and Oregon) as well as Canada, France, and Ireland, but products labeled for professional use in salons don't have to be labeled with their ingredients, according to Sigurdson. It could be why formaldehyde-free products can still contain the chemical - an unfortunate finding in a 2011 EWG investigation.

"In general, the alternatives [to formaldehyde-containing keratin treatments] are better," Andrews says, speaking to the severity of side effects caused by straighteners that are labeled free of formaldehyde. "But most of these treatments still have the potential for allergic reactions and sensitization with repeat usage."

6. The active ingredient in Japanese thermal hair straightening can mess with your health too. Japanese thermal hair straightening products might not contain formaldehyde, but they do expose you to ammonium thioglycolate, an irritant that can cause hair breakage at best, or trigger an allergic response at worst, according to the EWG.

7. Even the safest salon chemical treatments aren't 100 percent risk-free (and they don't work quite as well). There are plenty of less harsh alternatives like Pravana Perfection Smoothout, which O'Toole recommends. But because life isn't fair, it doesn't work quite as well as keratin. Other keratin alternatives can still contain ingredients like cyclopentasiloxane, which can release small amounts of formaldehyde into the air when heated by a blow-dryer or flat iron.

8. You do not want to chemically straighten your hair while you're pregnant or trying. Exposure to formaldehyde could affect your fertility or lead to miscarriage when you're pregnant, according to the Centers for Disease Control (CDC). It's why stylists like O'Toole refuse to treat pregnant women - and worry about the chemicals in general. "When the manufacturers say not to use [their product] on pregnant women, that should be the first clue that their products are unsafe," says O'Toole, who was a huge fan of keratin treatments before she began to experience adverse effects from chemical exposure, and left her old salon to avoid it. The jury is out on whether exposure can permanently affect your fertility.

9. Most precautions salons take to protect you and salon workers from fumes - like using a vacuum extractor - don't do all that much. O'Toole says her old salon used this kind of machine but she still experienced adverse side effects. "Some salons offer clients a surgical-type mask for clients, but that does nothing," she adds. (The CDC confirms this.)

10. If your salon offers chemical straightening, you're probably exposed to chemicals regardless of whether you're there for that treatment. Tests performed by the U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) found formaldehyde in the air exceeded permissible limits in salons where the treatment is offered.

11. At-home keratin smoothing treatments can contain some potentially dangerous chemicals too. If formaldehyde itself isn't listed on the label, it could still be present in the form of ingredients that sneakily contain or release it, such as methylene glycol, formalin, methylene oxide, paraform, formic aldehyde, methanal, oxomethane, oxymethylene, or CAS Number 50-00-0 on product labels, and formaldehyde-releasing ingredients include timonacic acid or thiazolidinecarboxylic acid. You may also want to look out for the disinfectant gluteraldehyde, which can trigger allergic symptoms or set you off if you're asthmatic, according to the EWG.

If a product's active ingredient is glycolic acid, alpha-hydroxyl acid, or keto acid, though, you should be in the clear.

12. Chemically treated hair could continue to release toxins even after you leave the salon. "It is possible that formaldehyde may be released to the air or react with skin [post-straightening,]" he adds, which could leave you exposed to harmful chemicals for longer than you'd banked on - particularly when heat styling with a curling iron, straightening irons, and blow-dryers, which could release irritating fumes.

13. Chemical straightening doesn't deliver pin-straight hair for everyone. "For those with extremely coarse and kinky hair, I would tell them not to expect pin-straight hair from the treatments, but more of a loosening of the curl," O'Toole says. "If you have very fine hair, I probably wouldn't have recommended these treatments, because it would make your hair too flat and lifeless," she says.

14. Chemical treatments can cause hair damage or loss - particularly if you've colored your hair. "I have seen some clients with fine hair that was damaged due to the product and temperature - especially if the hair was also color-treated," says Wynne Sisk, a stylist and founder of Green Mission Possible in Charleston, South Carolina. "Some clients have experienced burnt hair that needed to be cut off. Hair does tend to be drier and have more static after even one treatment."

Kelly Merriman, a stylist from Joliet, Indiana, has seen the same sort of thing. "Every client is different, it's a gamble," she says. "Some clients have many treatments and never have any problems, while others have just one treatment with lots of steady hair loss."

15. Despite its side effects and risks, chemical straightening can be addicting. "The process can feel life-changing," says O’Toole. "It becomes addictive, where at the first sign of frizz, [clients] are back in the chair," she says.

16. The more times you chemically straighten your hair, the greater your risk of developing symptoms. Formaldehyde is a sensitizer, which means after you reach a certain level of exposure and react to it once, Sigurdson says, you'll always experience allergic reactions when you encounter formaldehyde fumes - bad news considering formaldehyde is found pretty much everywhere: It's a byproduct of combustion and car exhaust, a component of wrinkle-proof fabrics, and found in some plastics and pressed wood products used in flooring and furniture. Because chemical hair straighteners contain much higher levels of formaldehyde than you're bound to encounter elsewhere, according to David Andrews, PhD, an EWG senior scientist, salon workers are particularly screwed.

17. Even stylists who swear by the amazing effects of keratin treatments don't exactly recommend them. "It's not worth the possible short-term effects, and absolutely not worth the long-term effects," says O’Toole, who tells people who ask her about smoothing treatments to look for safer alternatives, like learning to love your natural texture.

And if you're dead set on pin-straight hair, the absolute safest way to get pin-straight hair is by using a flat iron - assuming you've got a steady-enough hand to keep the hot plates away from your scalp.

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How bad is chemically straightening your hair? ›

Using chemical hair straighteners may increase the risk of uterine cancer, fibroids, breast cancer and endometriosis, according to studies. Side effects of frequent chemical hair straightener use include weakening of hair, increased frizz, hair discoloration and scalp inflammation.

What are the benefits of chemically straightened hair? ›

5 Benefits of Permanent Straightening
  • It straightens, naturally moisturises and conditions the hair.
  • It removes curls, frizz & controls unwanted volume.
  • It gives you straighter, smoother hair that always looks natural.
  • It's safe and formaldehyde-free.
  • It gives you long-lasting straight, smooth & manageable hair.
Feb 6, 2020

How long does chemically straightened hair last? ›

Permanent hair straightening done in a salon lasts anywhere from 4 to 6 months. Hair rebonding lasts about 5 to 7 months. Japanese hair straightening lasts up to 6 months.

Why does chemically straightened hair not last forever? ›

Because the keratin molecules are in different positions when the bonds are reformed, the hair stays in the straightened shape for a long period of time. As most people who use flat irons know, this method of straightening hair is not permanent. Exposure to moisture causes the hair to revert back to its original shape.

What is the safest hair straightening method? ›

Keratin Treatment (Brazilian Straightening)

They are one of the safer hair straightening techniques out there. Keratin is a natural protein that is already found in our hair, however as protein content decreases with age and a poor diet, so do keratin levels.

What is the least damaging hair straightening method? ›

Blow Dry + Smoothing Serum:

By far the least damaging to your locks than the rest of the list, this easy-to-do process removes water from hair via heat styling and resets it straight. “Make sure to use a heat protecting serum to help seal the hair, and use a lower heat setting while blow drying,” says Dr.

Is chemical straightening worth it? ›

There are no health benefits of a chemical hair straightening. It uses harsh chemicals in its formulas, which can possibly result in skin burns and over-processing if left on too long or if the hair technician does something wrong or is careless.

How often can you chemically straighten your hair? ›

We recommend you do not have your hair relaxed more than once every three to four months. The chemicals used in relaxing treatments are very strong and are applied near to your scalp.

How do you take care of chemically straightened hair? ›

Haircare Tips for Straightened Hair
  1. Do Not Shampoo immediately. For at least three days after hair straightening, do not wash your hair. ...
  2. Avoid Shampoos with Sulphate. ...
  3. Keep It Hydrated. ...
  4. Good Hair Care Regime To Prevent Hairfall. ...
  5. No Artificial Heat. ...
  6. Get Rid of Split Ends on Time. ...
  7. Oil It Up.
Apr 21, 2021

How do you sleep after permanent hair straightening? ›

Sleep flat on your back so your hair stays straight.

If you sleep on your side or stomach, your hair may get creased or frizzy. Try to position pillows or a folded blanket around your body to prevent you from rolling over to your side. This might help you stay on your back.

What not to do after permanent hair straightening? ›

Avoid any form of moisture e.g. excessive perspiration and saunas etc for at least 48 hours after the treatment. Keep your hair as straight as possible i.e. refrain from using hair clips, putting hair behind ears and avoid wearing hats or other head wears for at least 48 hours after the treatment.

What happens to your hair when you stop straightening it? ›

What's actually happening here is that the decrease in heat styling means there's less likelihood of breakage or split ends—both of which can cause your hair to feel like it's never growing and appear scragglier.

How long after chemical straightening can I color my hair? ›

Q: Can I have permanent hair straightening and colour at the same time? A: No. If you colour your hair at the salon, it should be done at least 2 weeks before or 2 weeks after the straightening procedure.

What is Japanese straightening? ›

Japanese Straightening, also known as thermal reconditioning, is a thio-based chemical procedure which uses heat to restructure the hair's protein bond, enabling those with frizzy, curly, or wavy hair to experience permanently straight hair while at the same time preserving the health and improving the feel, texture, ...

Which is better straightening or keratin? ›

Both The Treatments Ensure Shiny, Soft And Frizz-free Hair. The Results Of Smoothening Last For 2-3 Months, While Keratin Therapy Results Last Upto 5 Months. Keratin Therapy Nourishes The Hair, Repairing It From Inside Out, And Adds Extreme Shine And Softness To The Hair.

What ruins straightened hair? ›

Any type of moisture in the air or your body temperature will cause your hair to revert back to its natural texture.” This means heat, rain, humidity, sweat, and even stress are not your friends when your hair is straight.

What is the best temperature to straighten hair without damage? ›

According to Jonathan Colombini, celebrity hairstylist and L'Oréal Paris expert, “fine hair textures should stay in the 350–375 degree range, but for more coarse or thick hair, 400–450 degrees is appropriate.”

Why do Japanese have straight hair? ›

Most people of East Asian descent have thick, straight hair. This corresponds with a SNP (rs3827760) in the EDAR gene which is involved in hair follicle development. The ancestral allele of this SNP is the A-allele. The G-allele is the newly derived allele that leads to the thick, straight hair.

Does chemically straightening hair get rid of frizz? ›

Chemical Hair Straightening: The Pros

The treatment tames frizzy hair, giving you sleek and smooth strands. Chemically straightened hair can last up to 6 months, which is perfect for people who always want a sleek look. Plus, if you do this treatment yourself, at-home kits are very affordable and fairly simple to do.

How much does it cost to permanently straighten your hair? ›

Permanent hair straightening costs about $550 with average prices ranging from $100 to $1,000 in the US for 2020 according to StyleCraze, but we know from experience that permanent hair straightening costs about $575 with average prices ranging from $250 to $800 or more in metropolitan areas.

How do I get my natural hair back after permanent straightening it? ›

You can't turn hair that has been straightened back into its natural curly state. It is a permanent irreversible change. You need to be patient for months at least to grow out your hair so that it is long enough to chop of the straight ends.

Will your hair fall out if you straighten it everyday? ›

7. Permanent Hair Loss. If you think that you can straighten your hair for years and restore its health by simply putting away your straightening iron one fine day, you are gravely mistaken. Repeatedly using chemical relaxants and heat styling tools can kill your hair follicles and cause permanent hair loss (1).

How do you moisturize chemically straightened hair? ›

Oil: A common misconception holds that one should not oil chemically straightened hair. The fact is that you should only avoid oil for the first week post the treatment while the chemical takes full effect. After that, oil proves to be one of the best natural moisturisers for your hair.

What oil is good for chemically straightened hair? ›

One of the best oils for straightening hair is coconut oil. On top of its protective properties, it is also known to be one of the most versatile and nourishing oils available. This hair oil contains natural fats that help keep your hair hydrated and your scalp nourished.

Which conditioner is best for chemically straightened hair? ›

  • L'Oreal Professionnel Hair Spa Deep Nourishing Conditioner,
  • Toni&Guy Nourish: Conditioner For Damaged Hair,
  • Biotique Bio Sea Kelp Fresh Growth Revitalizing Conditioner,
  • Biotique Bio Neem Margosa Anti-Dandruff Shampoo & Conditioner,
  • L'Oreal Professionnel Hair Spa Detoxifying Conditioner,

Why won't my hair lay flat after straightening? ›

Hair that's dried out and brittle before you even start with the straightener is the culprit behind frazzled hair that won't lie flat. "Take a paddle brush to comb the conditioner through," suggests stylist Sarah Potempa (who's worked with Lea Michele), "then rinse your hair gently.

What happens if I dye my hair after permanent straightening? ›

Nonetheless, oxidation can weaken your hair's structure and may potentially cause permanent damage. The negative effects of oxidation can worsen if you combine hair color and hair straightening. That said, a lot of hair experts advise against coloring and straightening.

What are the do's and don ts before hair straightening? ›

It is important to dry your hair before using the straightener. Once you have washed the hair, dry your hair with a towel. Towel dry would take away a lot of moisture from your hair. Use a blow dryer to dry the remaining moisture in the hair.

How should I sleep the first day of hair straightening? ›

If you want your hair to stay straight, sleep straight on your back. Make sure your hair is straight below your head when you climb into bed. After that, carefully place your head on your pillow so that your hair is flat. For the first three days following a keratin treatment, sleep on your back.

How many days should I leave my hair straightened? ›

If you don't wash your hair, temporary straightening can keep your hair straight and healthy looking for about three to four days and will probably start returning to its natural texture or start losing the shine. Certain reasons that interfere with the duration of your temporary straightened hair are mainly.

Can I wash my hair daily after permanent straightening? ›

Wait at least three days to a week before washing your hair: "Your hair is in a fragile state after you've gotten it straightened," says hairstylist Ted Gibson.

What happens if you shower after straightening your hair? ›

The short answer is yes, you can shower after straightening your hair. The problem, however, is that as soon as your hair comes in contact with the water, it will revert back to its natural default. If your hair is frizzy, it will return to its frizzy state after the water begins drying out of it.

Does your hair grow slower if you straighten it? ›

Reduced hair growth

The chemicals and heat that are used to straighten your hair, do significant damage to your hair cuticles, in turn slowing down the speed at which your hair grows.

Why do I lose so much hair after straightening? ›

Hair that has been chemically treated is relatively drier than normal hair. This can often be a cause of hair loss and hair breakage. Deep conditioning your hair can help add moisture lost and maintain healthy hair volume.

What happens if I don't straighten my hair for a month? ›

For a month

"You would have recovered the hydration, the natural oils of your hair and would have strengthened the protective layer of the hair." Wood adds that this will improve the quality, texture, and density of your hair, and your curls and waves will become more defined.

Can you reverse chemical hair straightening? ›

Unfortunately, there is no way to reverse this chemical straightening treatment. The best thing to do is nourish your virgin hair that is growing in and trimming your hair at the rate it's growing to avoid extensive split ends. I would highly advise that you minimize or eliminate heat tools.

Can chemical straightening cause hair loss? ›

Conclusions: Straightening techniques can have side effects, including scalp inflammation, damage to the shaft, and hair loss.

Can you straighten hair without damaging it? ›

Instead of going for the conventional, opt for cool air while drying. Use a flat brush and go section-by-section by simultaneously blowing air. This process is likely to take more time, so avoid it if you are in a hurry. This is a great way to straighten your hair without using any kind of heat.

How many times can you chemically straighten your hair? ›

However, new hair will grow according to its natural texture. We recommend that you get permanent straightening touch-ups every 4 to 6 months, but the time frame will vary depending on your natural hair texture and how quickly your hair grows.

Can hair grow back after chemical damage? ›

Yes. Treatment for hair loss from chemical trauma can help to not only promote regrowth, but also to restore the hair's condition and strength.

What happens when you stop straightening your hair? ›

What's actually happening here is that the decrease in heat styling means there's less likelihood of breakage or split ends—both of which can cause your hair to feel like it's never growing and appear scragglier.

What temperature will damage your hair? ›

Exposure to high heat changes the shape of your hair's keratin strands. Temperatures over 300°F convert the ⍺-keratin to β-keratin, which eventually leads to weaker hair that has lost its elasticity and become more prone to damage.

Is it OK to straighten hair once a month? ›

"You should not flat iron natural hair more than once a month, especially if your hair is color-treated or damaged," says Powell. "Even once a month can be considered pushing it, so if you are flat ironing that frequently, it's important that you are hyper-aware of your hair's health."

Is it OK to straighten wet hair? ›

Using a normal flat iron to straighten wet hair should be avoided at all costs. Even if your hair is just slightly damp, your strands are still at risk for intense damage. Ultimately, the only time you should be picking up a flat iron to style your hair is when it's 100 percent dry.

Which is better keratin or straightening? ›

Both The Treatments Ensure Shiny, Soft And Frizz-free Hair. The Results Of Smoothening Last For 2-3 Months, While Keratin Therapy Results Last Upto 5 Months. Keratin Therapy Nourishes The Hair, Repairing It From Inside Out, And Adds Extreme Shine And Softness To The Hair.


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