By Jc of The Nat­u­ral Haven Bloom
recent­ly dis­cussed the key role of SLS. It can clean oil off hair by caus­ing the oil to dis­solve in water. This oil film on hair is the main source of dirt. The oil film that sur­rounds the hair allows dust, fluff, lint, smoke par­ti­cles, dead cells etc to stay attached to hair. Get­ting rid of this oil film is the prin­ci­ple func­tion of SLS.

The next ques­tion is does SLS break hair?
Break­ing hair is not quite the right term. When hair is washed even with plain water, some pro­tein will be found in the water. This may in part come from break­age but it may also result from nor­mal wear of hair (i.e part of the cuti­cle is already weak and then falls off).

How do we know that pro­tein comes off when hair is washed?
The sim­plest test is to place some hair in a con­tain­er of water and shake it around. After a few hours, the hair is removed and the water is test­ed to see how much pro­tein came off the hair.

How much pro­tein comes off?
Not much is the answer. One study which per­formed this test for 24 hours with dif­fer­ent solu­tions is real­ly use­ful for our pur­pos­es. (J Soc Cos­met Chem, pp163-175,1993).

Here is a table show­ing how much pro­tein they detect­ed in the study.

Solu­tion Amount of pro­tein (mg/g)
Water 8.4
Sodi­um lau­ryl sul­fate (SLS) 10.3
Ammo­ni­um lau­ryl sul­fate (ALS) 9.4
Ammo­ni­um lau­ryl ether sul­fate (ALES) 8.1
Sodi­um lau­ryl ether sul­fate (SLES) 7.6
Sodi­um deceth 3 sul­fate (SDES) 6.6

Tak­ing water as our base­line, we can see that not all sul­fates were cre­at­ed equal. High­light­ed in yel­low, the very effec­tive cleansers have more pro­tein debris than water. How­ev­er oth­er sul­fates have less pro­tein com­pared to water (high­light­ed in green).

Is there evi­dence that using SLS caus­es hair break­age?
One study on SLS report­ed that  they would pre­dict dai­ly sham­poo­ing (with SLS) would lead to comb­ing dif­fi­cul­ties with­in a year and split ends with­in 3 years due to cuti­cle deple­tion. (Col­loids and Sur­faces B: Bioin­t­er­phas­es, pp 7.14, 2005)

In my opin­ion this is stat­ing the obvi­ous. Stud­ies look­ing at how hair changes as it gets old­er have already doc­u­ment­ed that the hair cuti­cle is sig­nif­i­cant­ly deplet­ed and com­plete­ly absent around the 20 inch mark (around 3 years assum­ing a 6 inch per year growth rate). (J Soc Cos­met Chem, pp 155–175, 1977).

Cuti­cle wear is more relat­ed to hair care prac­tices than SLS use.

To cut a long sto­ry short, any time you han­dle your hair, you dam­age it. There is no way to elim­i­nate this but the dam­age sus­tained can be min­imised by gen­tle han­dling of hair.

Note for accu­ra­cy: Using the word sul­fate (sul­phate) is not quite accu­rate.  The sul­fate part of sodi­um lau­ryl sul­fate is actu­al­ly pret­ty harm­less.  How­ev­er in the curly world , the term sul­fate sham­poo is com­mon­ly rec­og­nized.


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13 Comments on "Can Sulfate Shampoos BREAK Natural Hair?"

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[…] used to be: hop in the show­er, wash with a sul­fate (yeah yeah…) sham­poo, strug­gle detan­gling it with comb, may­be deep con­di­tion or pro­tein treat every week […]

lashaunda motley

I have been using sul­fate sham­poos for a long time and I have not had any prob­lems with my hair being dry our dam­aged. As long as you keep your hair mois­tur­ized and stick to your dai­ly rou­tine, you won’t need to wor­ry.

Tina Faye

I have fine, wavy hair that tends toward dry­ness and frizzi­ness. I use about a dime-sized amount of the Shielo Antiox­i­dant Leave in Pro­tec­tant on wet hair and then air-dry. I end up with shiny, wavy, frizz-free hair, which is amaz­ing since I’ve tried pret­ty much every frizz-fight­er around. Also, after a mon­th I noticed my hair is break­ing a lot less and over­all look­ing health­ier. Plus, the smell is amaz­ing. Great pro­duct!


I know sul­fates are what make sham­poos sudsy. I made sure mine didn’t have any, I got a good one based on argan oil and the dif­fer­ence is notice­able, less hair loss and frizz :) Real­ly lov­ing this sham­poo! I got it online at and I’m plan­ning on get­ting the con­di­tion­er and moroc­can argan oil too.


I don’t use sul­fate sham­poos because they dry out my hair and that in turn caus­es my hair to break and split. I actu­al­ly just recent­ly stopped using sul­fate sham­poos and every­one keeps com­ment­ing on how shiny and healthy my hair looks. I nev­er though I would stop sham­poo­ing but I’m now a no-poo con­vert…


“To cut a long sto­ry short, any time you han­dle your hair, you dam­age it” That’s a lit­tle off putting, isn’t it? Every time the hair is han­dled it is dam­aged? Define “dam­age.”

Miss O

This would be a bet­ter study if it was done on dif­fer­ent hair types. Everyone’s hair is dif­fer­ent. There­fore reacts dif­fer­ent­ly to dif­fer­ent com­pounds.

Michelle @Radiant Brown Beauty

I agree. When my hair was relaxed and I didn’t know any bet­ter, i used sham­poo with sul­fates and my hair was long. It’s get­ting long now after sev­er­al cuts and I don’t use sul­fate sham­poo but hon­est­ly I’ve nev­er had hair break­age from using sul­fate sham­poo. May­be it’s because I also made sure my hair was suf­fi­cient­ly mois­tur­ized which I think is the key regard­less of the type of sham­poo you use. sul­fates may dry the hair out but mois­ture will coun­ter act that.

Jo Somebody

Prob­a­bly a sil­ly ques­tion, but was the ‘nat­u­ral’ in the title inten­tion­al? Do SLSs or even water dam­age relaxed/coloured/other processed hair more?

Any­way, this is good to know (although I agree soak­ing for hours doesn’t reflect what hap­pens out of the lab, but then again, may­be they did that because they weren’t doing the hair rub­bing that DOES occur dur­ing hair-wash­ing). How­ev­er, for me, the dam­age of sul­fates is to exces­sive­ly dry out my scalp and hair, mak­ing my hair more tan­g­ly, which THEN leads to los­ing hair.

Here’s what I don’t get about people’s wor­ry about SLS: it’s not based on the more wor­ry­ing fact that SLS fast tracks xenoe­stro­gens direct­ly into your blood­stream (since you’re apply­ing SLS sham­poos onto skin, which has no bar­ri­er unlike when you ingest prod­ucts). For the life of me, I don’t know why this isn’t added to the SLS con­ver­sa­tion. Hon­est­ly, I think this is far more seri­ous than break­ing hair. We’re talk­ing about fast-track­ing chem­i­cals that mim­ic estro­gen. I’m sor­ry, but I had to write this. And the last time I men­tioned this, there was a respon­se that seemed like… Read more »
There are sul­fates in every­thing thats meant to clean some­thing from dish­es to tooth­paste to facial cleansers to body­wash. Are we real­ly going to stop using things because of what one research study shows??? its a lit­tle ridicu­lous to even use this as a basis for what it can and cant do for anyone’s hair because like some­one said, we dont soap hair for hours for any­thing of this mag­ni­tude to hap­pen. And more impor­tant­ly is what you do to your hair AFTER you use a clar­i­fy­ing shampoo…As a nat­u­ral hair styl­ist from Atlanta, I can tell enough of my… Read more »

Why does the base­line call for the hair to be soaked for hours? We don’t soak our hair in solu­tion when we waah it, specif­i­cal­ly not for hours, which in and of itself could cause dam­age by swelling of the hair strand.


this is educa­tive