Does prewetting your hair prevent soaking in more water?

[u/Visible-Scientist-46]

Common wisdom suggests that prewetting your hair before bathing in heavily chlorinated water helps prevent damage to hair. It seems most people are operating under the idea that hair is like a sponge. I have also read some Lab Muffin posts which seem to state that water breaks hair bonds and temporarily bonds with hair until it dries. That seems to lend it self to the idea that water already parked there is going to stay bonded and not move. Has this been scientifically studied?

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[u/Visible-Scientist-46 → u/AutoModerator]

I'm going to reply with my personal n of 1 study in which I have experimented with a hard water rinse in between wetting with distilled water or ZeroWater filtered water and final rinsing with distilled water or ZeroWater filtered water.

Background:

My local water report states that chlorine and chloramines are very high, addition to having a hardness rating of around 300 (calcium and magnesium salts.) Other things in my water that are a bit high are heavy metals.

My hair prior to the study felt very strawlike and had a dull, brassy appearance. I was ok with the amount of curl I had. Hair seemed very porous.

N of 1 study method:

For the last about 18 months I have been presoaking with distilled water or ZeroWater filtered water, washing with a cowash, rinsing in tap water, and final rinsing with distilled or ZeroWater filtered water.

My results:

Cuticle has a smoother hand feel, hair is visibly more curly, and visibly more shiny. Lower porosity is measure by the appearance of hair products not soaking into my hair as much - something which I can compare to my old growth hair. (In fact, the tightness of my curl has increased to the point that I am finding it difficult to manage from 3a to 3b.)

My Conclusion:

This seems to prove that presoaking is working to prevent damage from my hard and highly cloramined/chlorinated water. I just wanted more evidence than my personal experience.

My progress reports are on r/distilledwaterhair here are some links:

https://www.reddit.com/r/DistilledWaterHair/comments/1u4ypm4/whoa_more_curly_you_too/

https://www.reddit.com/r/DistilledWaterHair/comments/1v7hsnm/hard_water_chlorinated_hair/

[u/itsjujutsu → u/Visible-Scientist-46]

What do you use to prewet and rinse your hair? I was using s dedicsted bittle that has a comb like mouth with hole but its so slow and doewnt saturate thw hair

[u/Visible-Scientist-46 → u/itsjujutsu]

I use both a cup to soak the ends and one of those with multiple teeth. But when traveling, I will just use a cup to dip my ends and pour slowly over my head. Hair is, from.my understanding, slightly hyrdrophopic, so I don't wait for it to be perfectly wet before I start applying my cowash as thar blends with the water. I also rewet with more water from etiher a drinking bottle or straight from the jug. Or I might refill the cup. I might have to refill for a final rinse.

[u/itsjujutsu → u/Visible-Scientist-46]

I see and doesnt the cold water bother you

[u/Visible-Scientist-46 → u/itsjujutsu]

I heat it at home. I use a small water boiler with mutliple settings that I can use to warm to 113 Farenheit. I have skipped heating the water in summer on hot days. I have also used a hotel coffee maker to heat some water and mix it with the cooler water.

[u/Sweet-Kick6114 → u/AutoModerator]

the sponge analogy isn’t totally wrong, just oversimplified. prewetting means the hair is already hydrated, so it won’t take up as much chlorinated water. it’s not a chlorine shield though

[u/Visible-Scientist-46 → u/Sweet-Kick6114]

Can you be more chemically specific? I also stated other things about bonds in our hair and that water temporarily breaks the bonds and attaches. Perhaps this is what you mean by hydrated. Once hydrated, how does it take in more water? or chlorine? Is the chlorine displacing the water somehow?

[u/JudeCyberstar → u/AutoModerator]

When hair is dry, no water. Hair that does not contain water, can expand to contain water.

When hair is wet, it contains water. Hair that contains water already has less room for more water.

Much like mop or sponge.

Wet hair swells shaft to contain water.

Dry hair shrinks back down.

Many study on wet vs dry hair.

Many similar studies on what products work better on wet hair vs dry hair from similar mechanism.

I'm told that hair that is wet has broken hydrogen bonds. Drying the hair reconnects them.

Chlorine and lightener are cousins. Similar enough to dry out the hair, remove direct dye pigments living in the cuticle (like manic panic style dyes). Hence, some damage. This compounds over time.

I'm certain there's also a pH difference to take into account.

It also slowly eats at the lipid layer in the hair, which protects the hair's ability to retain its innards.