Why do some people’s roots dry faster than their ends?

[u/thebddone]

This might be a silly question, but reading online, it seems most sources agree that the roots of the hair tend to dry slower than the ends. The most common explanation being that the ends tend to be more porous than the roots, which seems very logical.

However, it seems some people’s hair does the complete opposite, having quick drying roots and slow drying ends. What could be the explanation for this?

[u/VonBoo]

Low density hair, better air flow plus heat from the scalp. 

Porosity, low porosity near the roots and higher porosity in the length ends can mean different drying times.

Conditioner, products, usage and techniques. With some hairtypes and products it's recommended to use it in the middle lengths and ends. This means the product and any water it's holding could have different drying times 

Gravity. Same as when you hang up something to dry. The top with usually dry first as the water works down the fabric.

[u/thebddone → u/VonBoo]

Thank you for your reply. I still don’t quite understand why this only applies to some people, whereas others experience the exact opposite

[u/VonBoo → u/thebddone]

I imagine hair type and density is large factor. Super dense hair can trap water to a point same with curls and coils where the where doesn't always have a downward trajectory to flow.

[u/AnywherePresent1998]

I always thought that it was because of gravity. The water goes down towards the ends and by the time you blow dry your hair the roots aren’t very wet

[u/thebddone → u/AnywherePresent1998]

That’s what I thought too, but turns out the majority of my friends experience the opposite, with the roots being last to dry

[u/soymilkerz]

Cos of the heat from ur scalp

[u/thebddone → u/soymilkerz]

Could you elaborate? How does this work and why does it affect people so differently in this case?

[u/RedSaguaro1013]

Its about hair porosity (how much water each strand absorbs and how quickly it loses that water). Hair porosity is determined by genetics, but can change with chemical processing, heat styling and anything else that damages or smooths the cuticle of your hair. You can read about it here..

Because of this, the same strand of hair can be less porous towards the root and more porous on the ends due to lightening or other damage.

Pretty much every source will say high porosity hair absorbs water easily and loses water easily, but that is dependent on the type of damage in my opinion.

If you're trying to dry someone who has damage from straightening their hair everyday, the ends typically dry extremely fast (& frizzy) because they are damaged, dehydrated and can't hold the moisture well. This is the same for a lot of people with natural curls. Their ends will typically be dehydrated and dry quickly unless they are moisturizing well.

If you're drying an overprocessed blonde, the ends are still high porosity, but they aren't going to dry quickly bc the water swells inside the cuticle bc of chemical damage. Chemical damage from overprocessing effects the cortex of your hair which is deeper than the cuticle. If you've ever seen a DIY bleach video where the person ends up with gummy ramen noodle blonde, that is overprocessed and will absorb the water easily while also taking forever to dry.

2 ways the ends dry slower due to porosity:

Normal porosity roots + overprocessed blonde = ends drying slower than roots

Low porosity long hair + blowdrying = water pushing down the hairshaft making the ends take longer to dry than the roots (can also happen due to gravity while air drying)

[u/thebddone → u/RedSaguaro1013]

Interesting. I recently talked to some of my friends about this and it turned out I was the only one whose roots dried quicker than my ends. I’ve never done any sort of chemical treatment and don’t heat style my hair, and I don’t think my friends do either, so I was really confused

[u/helpmeoutpleaze]

Scalp has natural body heat too! Scalp heat and gravity baby

[u/thebddone → u/helpmeoutpleaze]

But why does it differ so much from person to person since it seems many people’s roots dry slower than their ends?

[u/helpmeoutpleaze → u/thebddone]

Ends have been exposed to more “damaging” factors (environmental, heat, styling etc) that increases porosity in the ends. They will always dry up slightly faster! Root hair is new virgin hair, cuticle is more closed.

Could also be medication.

Sometimes with my clients that have lower porosity hair or clients that use a lot of non water soluble silicone products I notice the ends take forever to dry. Sometimes I’ll put a little mousse in on the ends on those people.

Sorry for the novel, I probably jumped around in the explanation too🤦‍♀️🤦‍♀️ morning brain😂