What Happens If You Leave Conditioner In Your Hair?

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We’ve all experimented with hair care products, recipes, and haircare methods in our quest for healthy, beautiful hair.

Many of us have tried shampoos, hydrating mists, and every type of conditioner on the market to get smooth and silky locks.

Some even go the extra mile and consider leaving conditioner in their hair for longer to moisturize it more.

But is this helpful, or does it cause more harm than good? Or does nothing happen at all?

Let’s take a closer look. What really happens after leaving conditioner in hair for more than a few minutes, like for an hour or even overnight?

Will this method be more effective in hydrating your hair, or will it do the opposite of what you want? Is there such a thing as over-hydration?

In this article, we’ll answer all your conditioner questions and share the best types of conditioners you can use and how to use them for gorgeous hydrated locks.

Is It Okay to Leave Conditioner in Your Hair Overnight?

So, is it ok to leave conditioner in your hair overnight? The simple answer is no. Sleeping with conditioner in your hair is not okay, especially if you use a regular rinse-out conditioner. This can have several harmful effects on your locks.

If you want to try overnight conditioning, you can use a leave-in conditioner product that’s meant to be left on your hair.

However, some people have used regular conditioners for more extended use without rinsing. When they do this, they dilute it with equal parts water and only apply it to the ends of the hair.

This can be done, but only on extremely dry, coarse hair and not regularly.

People who have tried this claim that it adds extra moisture to their locks that lasts throughout the day.

But isn’t that precisely what a leave-in conditioner does? In a way, yes, and it’s a better alternative for extended conditioning.

How Do Conditioners Work?

If you’re thinking about leaving conditioner in your hair overnight, it’s probably because your locks are really dry. Understanding why your hair is dry will help you understand what products to use to remedy that and how to use them.

Your hair may lack moisture because of several factors. You might have naturally dry, low porosity, or high porosity hair. Or your hair may be dry due to overuse of harsh products like hair dye, bleach, or shampoo.

Dry and damaged hair is hard to manage. Plus, it’s unhealthy. And unruly and unhealthy hair is more than just a cosmetic concern. It can also impact your confidence. 

And that’s where a conditioner can help. Conditioner helps replenish the lost moisture in your strands. It also ensures that your hair is hydrated, free from tangles, and protected from damage.

But how do they do this? Let’s take a closer look at how conditioners work.

Ingredients and Formulation

The formula used in conditioners is responsible for how this incredible product works.

Conditioners contain positively charged cationic surfactants. These surfactants cling onto the surface of your hair strands, which carry a negative charge when wet, creating a protective film.

This film coats the hair and smoothens it, making hair softer, removing tangles, and making it easier to comb.

These are also responsible for the slippery feeling your hair gets after washing. The coating also protects the hair shaft and helps it retain moisture for several hours after use.

Other Ingredients in Conditioners

• Oils
• Silicones
• Emollients

All these substances help make your locks softer and smoother after conditioning.

Plus, some conditioners have added nutrients like protein and natural oils to help mend the damage caused by coloring, heat styling, and environmental triggers.

Types of Conditioners and How to Use Them

Now that you know how conditioners work, you’ll understand why it’s essential to include conditioners in your hair care routine.

However, different conditioners cater to different hair needs and hair types. The way each type of conditioner is used differs too.

Rinse-out Conditioners

This is the standard type of conditioner that you use every time you shower. Although it is most commonly used after shampoo, some also use this conditioner without shampooing first.

How to Use a Rinse-out Conditioner

1. After shampooing, gently wring out the excess water from the hair.
2. Apply the conditioner from mid-shaft to ends. Don’t use conditioner on your scalp.
3. Leave it on for 3 to 5 minutes, then rinse well.

The American Academy of Dermatology (AAD) recommends using a rinse-out conditioner after every wash, concentrating mainly on the tips of your hair.

However, if your hair is oily or fine, use this product sparingly to avoid weighing your hair down.

Plenty of conditioners are available in the market, and one of our favorites is OGX.

OGX shampoos are famous for their moisturizing properties, and their sulfate and paraben-free conditioners like OGX Nourishing+ Coconut Milk Conditioner are perfect for hydrating and smoothing hair. 

Leave-in Conditioners

This conditioner type is made with a lighter formula than regular conditioner. That’s why leaving this conditioner in your hair is okay until the next wash.

Leave-in conditioners are usually made with oil or humectants like glycerin to help moisturize the hair without weighing it down. 

The formulations for leave-in conditioners are designed to detangle and add moisture balance to your locks, which stays even after drying and styling.

How to Use a Leave-in Conditioner

1. After your shower, gently towel dry your hair to remove excess water. 
2. Apply the leave-in conditioner to damp hair, following the product label’s instructions.
3. Comb through your hair gently using a wide-tooth comb or your fingers.
4. Let your hair air dry and style as desired.

Using a leave-in conditioner twice or even thrice  a week is typically enough. But if your hair is dry, damage, or curly you should use it more often.

A good leave-in conditioner we recommend is Marc Anthony Grow Long Super Fast Strength Leave-in Conditioner. It’s infused with biotin, caffeine, and ginseng to promote stronger, healthier hair.

Deep Conditioners and Hair Masks

Deep conditioners and hair masks have heavier formulas that are good for treating very dry and damaged hair.

Deep conditioners and hair masks have more concentrated emollient and humectant ingredients. That’s why they are perfect for more intense conditioning.

They also target specific concerns like

• Repairing,
• Hydrating
• Strengthening

These types of products give instant results. You’ll notice your hair is softer, smoother, and less dry after use.

How to Use a Deep Conditioner

1. Section your freshly washed, towel-dried hair using alligator clips.
2. Apply the product starting from the tips and working your way up.
3. Comb through your hair for even coverage.
4. Wear a shower cap and wait 15 to 30 minutes to let the product work.
5. Leaving conditioner in hair for an hour or more can also be done if your locks need extra moisturizing.
6. Rinse your hair thoroughly, then air or blow dry it as usual.

Check out this video for a more detailed tutorial for deep conditioning your locks.

Deep conditioners and hair masks can be used once or twice a month or even more if needed. There’s no standard frequency for using these products. It depends on your hair’s needs.

You can listen to your hair. When your tresses feel straw-like and frizzy, it’s time to get your intensive conditioner.

Try Shea Moisture Manuka Honey & Mafura Oil Intensive Hydration Hair Masque. This mask also has fig extract and baobab oil, perfect for hydrating and pampering your hair.

Cleansing Conditioners

There is also a conditioner that can cleanse and condition your hair simultaneously. It’s not a 2-in-1 shampoo and conditioner. It’s a cleansing conditioner or more popularly known as co-wash.

These conditioners are lighter than rinse-out types and have additional nonionic surfactants that cleanse the hair without the lather. That’s why it can be used in place of shampoo when washing your hair.

The Curly Girl method prefers this product because it’s less drying than shampoo.

For healthy hair care, we recommend Aunt Jackie’s Flaxseed Recipes Purify Me Moisturizing Co-wash Cleanser. It’s an excellent product for natural curls, coils, and waves.

What Happens After Leaving Conditioner in Hair Overnight?

Now that you better understand the different conditioner types, we hope it’s clear why the only conditioner you should leave in your hair without rinsing is the leave-in variant.

But what about putting conditioner on dry hair overnight and rinsing it the next day? 

Sometimes in our desire for quick and noticeable results, we go to great lengths. If conditioner is good for 3 minutes on the hair, isn’t overnight even better?

While the logic seems sound, it’s not necessarily true. Letting a product with unnatural chemicals stay in your hair longer than needed could potentially do more harm than good.

And while doing it once may not cause instant damage, persisting in doing it often may adversely affect your strands.

On the whole, sleeping with regular conditioner in your hair is not a good idea. Here are some issues that may arise from doing this or over-conditioning your hair.

Hygral Fatigue

This condition is the repeated swelling and deswelling of the hair strand. As you know, hair is porous. It absorbs water and moisture. And when it does, it swells.

As the strand expands, it creates tension that causes hygral fatigue.

The swelling and de-swelling can cause physical stress to your hair structure that may result in the following:

• Degeneration
• Loss of hair coating
• Lack of elasticity
• Raising of hair cuticles

What does the swelling have to do with leaving your conditioner overnight? When you put conditioner on your locks, they become wet, making them swell.

Moreover, leaving conditioner in for a long time will absorb the product deep into the hair cortex. This may cause moisture overload and which results in hygral fatigue.

Signs of Hygral Fatigue

• Frizzing
• Tangling
• Dullness
• Brittleness
• Gummy strand texture
• Constant hair breakage

Hygral fatigue may happen no matter what type of conditioner you use because the issue is when you’re using too much moisturizing products.

How Do You Treat Hygral Fatigue?

• Reduce the frequency of hair washing for a few weeks.
• Take a break from hair moisturizing products.
• Use a shampoo that’s low in pH.
• Reduce causes of damage, like chemical treatments and heat styling.
• Use coconut oil hair treatment.
• Trim the damaged hair.

Product Buildup

Most conditioners have heavier ingredients meant to be washed out after use. They will likely pile up on your scalp if you leave them on your hair.

Some of these ingredients that may build up include simethicone, dimethicone, trimethicone, polydimethylsiloxane, and phenyl trimethicone, to name a few. These weren’t meant to stay in the hair outside of the shower.

When these products build up on your scalp and hair, it’ll start to feel sticky and eventually might begin to itch.

Product buildup can clog the hair follicles too. When this happens, oxygen and other nutrients won’t be able to reach your roots. This can lead to folliculitis or infection of the follicles and even hair loss.

Scalp Irritation

Another thing to be worried about regarding product buildup is its effect on your scalp.

When sebum, hair products, and dead skin cells accumulate on your scalp, flakes may appear due to irritation.

Other than flakes, you may also notice

• Redness
• Itchiness
• Oily or crusty skin.

This buildup can result in skin conditions like dandruff (seborrheic dermatitis), scalp psoriasis, or atopic dermatitis.

Flat and Limp

The natural oils and the chemicals you leave behind by leaving your conditioner in for too long can weigh down your hair, making it look limp, unruly, and unhealthy.

And last but not least, not rinsing out the conditioner can also attract dirt and dust, causing your locks to lose their luster.

What Can You Do for Better Hair Hydration?

Now that you better understand the potential risks of leaving regular conditioner in your hair too long, you know that doing it too much won’t always benefit your tresses, no matter how smooth they feel after a condition.

After all, anything in excess is bad. So how do you hydrate your hair better? Stick to the tried-and-tested haircare basics!

Instead of using a regular conditioner as a leave-in conditioner, use the right leave-in product in the right amount for the right amount of time. Plus, be sure to buy the right kind of conditioner to address your specific hair needs.

Here are some other ways you can ensure your hair is properly hydrated:

Tips on Keeping Your Hair Hydrated

• Wash your hair and condition it safely using sulfate and paraben-free shampoo and conditioner suited for your hair type.
• Use a rinse-out conditioner in your hair every time you shampoo, but make sure not to leave it in your hair for more than 15 minutes.
• Follow the instructions when you use a conditioner of any type.
• Use a leave-in conditioner that won’t weigh down your hair if you want to leave the conditioner in longer.
• If you want overnight hydration, use a natural ingredient like coconut oil which is proven to help prevent hygral fatigue.

FAQs About Hair Conditioner

Is It Bad to Leave Conditioner in Your Hair Overnight?

It can be harmful, yes. When you leave rinse-out conditioner in your hair overnight, you may over-condition your tresses, which can negatively impact your hair health and cause your locks to become brittle.

Can I Use a Regular Conditioner As Leave In?

Even though some people may say that you can use a regular conditioner as a leave-in because it has similar contents, we wouldn’t recommend it.

After all, a rinse-out conditioner is designed to be rinsed out (hence the name). If you want to keep your locks moisturized, use a good leave-in conditioner instead.

And especially don’t try leaving deep conditioner in hair overnight as this is definitely too much moisture.

Get the Best Results by Using Conditioner Properly

Whether you have straight or curly hair, fine or thick, dry or oily, there’s a type of conditioner for your needs. Using the right conditioner in the right way is the best way to care for your locks and leave your hair soft and smooth.

Conditioning products are designed to help us care for our hair. The best way to get the best results is to use these products as they were intended.

Be sure not to leave a rinse-out or deep conditioning conditioner in your hair for longer than instructed to avoid damage. Remember that too much of a good thing can be bad too.

If you want smooth and silky strands, get the best conditioner for your specific hair needs and follow the product’s instructions, and you’ll surely get your desired results.

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