Is Japanese Hair Straightening Safe While Breastfeeding? (Explained)

Japanese hair straightening is a popular way to chemically straighten hair without the risk of heat damage. It is especially common for moms who are breastfeeding to use the Japanese hair straightening technique as it is considered a safe method for nursing moms. 

Japanese Hair Straightening While Breastfeeding

In this article, we will expand on why it’s safe for nursing moms to do Japanese hair straightening, precautions to take, and how often to straighten their hair.

We will also answer questions concerning the effect the chemicals from Japanese hair straightening can have on a nursing mother’s milk supply.

Is It Safe to Do Japanese Hair Straightening While Breastfeeding?

Scientific studies have shown that Japanese hair straightening does not have any negative effects on a breastfeeding mother or her baby. It is, therefore, safe to perform for nursing moms. 

Other forms of chemical hair straightening such as Brazilian hair straightening and keratin smoothing contain carcinogenic and mutagenic chemicals. These could be harmful to nursing babies. 

However, Japanese hair straightening employs different chemicals, none of which have been shown to be mutagenic or carcinogenic. 

As long as the Japanese hair straightening you’re using does not have formaldehyde (which it shouldn’t), then it should be safe to use for a nursing mother. 

What Precautions Should a Nursing Mom Take If She Gets Japanese Hair Straightening?

What Precautions Should a Nursing Mom Take If She Gets Japanese Hair Straightening

If you choose to get your hair Japanese straightened while you are still breastfeeding, you need to take a few extra precautions.

This is to ensure that your baby does not become exposed to the chemicals, despite their non-mutagenic properties. 

After getting your hair done, always take a shower. Make sure to thoroughly clean your chest so there is no chance of lingering chemicals. 

Do this before you nurse your baby. Keep your hair tied back or cut short so that the chemicals in your hair don’t constantly come into contact with your baby.

Always check that the product being used either by you or your hairdresser is marked safe for nursing moms. 

If there is any doubt or question, ask your doctor or find an alternative product to use.

How Often Can A Breastfeeding Mom Do Japanese Hair Straightening?

Japanese straightening treatments should be limited for moms who are still breastfeeding. This is to avoid unnecessary exposure of chemicals to their baby. 

That being said, most Japanese straightening treatments usually last for six to twelve months. The average nursing mom may therefore only receive a maximum of four treatments while she’s still breastfeeding. 

To err on the side of caution, it may be best to extend the typical time period between treatments. 

For example, instead of getting your hair Japanese straightened every six months, go every twelve months while you are still nursing. 

This will help reduce the risk of exposure to your baby. 

If you feel you need to get your hair straightened more often than that, talk to your doctor or your child’s pediatrician to see what course of action they would recommend. 

Will the Chemicals from Japanese Hair Straightening Affect a Nursing Mom’s Milk Supply?

Will the Chemicals from Japanese Hair Straightening Affect a Nursing Mom’s Milk Supply

There are no studies to show that the chemicals used in Japanese hair straightening treatments affect a nursing mom’s milk supply. 

The chemicals should affect milk production, nor should they show up in the milk itself.

Since the chemicals are absorbed through the hair, there is very little (if any) amount of chemicals that will show up in a nursing mom’s milk supply. 

Chemicals absorbed through the skin may have a higher impact. Therefore, be sure to wear protective clothing (and gloves if you’re self-applicating) to avoid skin absorption.

To be extra safe, wait at least two hours after your Japanese hair straightening treatment before nursing your baby again. 

The best way to plan or schedule your hair treatment is to have it done right after you nurse.

This is to allow the maximum amount of time between the treatment and your next breastfeeding session.  

What Alternatives to Japanese Hair Straightening Are There for Nursing Moms?

If you are still leery of using Japanese hair straightening during breastfeeding despite the safety assurances, there are chemical-free alternatives for straightening your hair. 

Applying products such as saffron smoothing treatment or soybean oil can naturally straighten hair without using chemicals.

Simply heat treating your hair by straightening it with an iron or a straightener rod are also possible options. These are less permanent and can cause damage if done too frequently or incorrectly. 

Another alternative is to live with and love your un-straightened hair until your baby is weaned. Afterwards, you can get back to your regularly scheduled Japanese hair straightening treatments. 

Is It Better to Japanese Straighten Hair at Home or in a Salon?

Is It Better to Japanese Straighten Hair at Home or in a Salon

It’s up to your personal preference whether your Japanese straighten your hair at home yourself or go to a salon to have someone else do it. 

It may cost more to have it done, but if you’re not used to doing it yourself, it may be the better option especially if you’re breastfeeding.

Salon professionals are guaranteed to have a clean space because of the various health and safety codes they must comply with. 

They will also know how to apply the treatment in an efficient and clean method to avoid unnecessary spills and overuse of chemicals.

Most importantly, if you go to a salon, you don’t have to worry about keeping the chemicals at home where they could be a danger to your little one. 


There are a lot of things to be wary of when you’re a nursing mom and avoiding chemicals is important to keep your milk supply healthy for your baby. 

However, there are some hair treatments such as Japanese hair straightening that have been shown to be safe for breastfeeding mothers. 

None of the chemicals used exhibit carcinogenic or mutagenic properties and no studies have shown that the chemicals are expressed in a nursing mother’s milk. 

To make sure that your baby isn’t unnecessarily exposed to the chemicals, have a professional Japanese straighten your hair. Limit your treatments, and allow at least two hours between treatment and your next nursing session. 

Japanese hair treatment is a great way to straighten your hair without damaging it using heat. It is safe for your baby and makes you look and feel like a fantastic mom. 

Frequently Asked Questions

Can I Do Japanese Hair Straightening When My Baby Is 5 Days Old?

You could get your hair Japanese straightened right after delivery if you wanted to. The method is safe and will not interfere with early milk production or supply. 

Can I Do Japanese Hair Straightening While I’m Pregnant?

Just like nursing moms, pregnant moms can also get their hair Japanese straightened because the chemicals in the treatment have not been shown to have any detrimental effects on a pregnant mom or her developing baby. It is recommended to limit treatments during pregnancy. 

Will My Baby Get Chemicals from Japanese Hair Straightening Through My Breast Milk?

There is no evidence that the chemicals used in Japanese hair straightening treatments are expressed in a nursing mother’s breast milk. Your baby should not have any issues unless there are known allergies to any of the chemicals, in which case it would be safer to avoid the treatment altogether. 

Can Japanese Hair Straightening Cause Postpartum Hair Loss in Nursing Moms?

As long as the Japanese hair straightening treatment is performed correctly, there should be no risk of hair loss. If you are experiencing postpartum hair loss, consult your doctor before applying a chemical hair treatment such as Japanese straightening. 


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Dee Poulsen

Dee has been following the Curly Girl Method for over four years and is our in-house Curly Girl expert. She has a keen interest in natural haircare and has tried and tested her share of CGM products. She has a photographic memory of most sulfate and silicone-free hair products available on the high street and she's always happy to recommend you her favorites.