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Knifegill
September 13th, 2014, 02:00 AM
People love vinegar and such on their hair, but there has to be a limit to how low the pH can get before it begins to dissolve hair, right? How low is too low?

Sarahlabyrinth
September 13th, 2014, 02:02 AM
People love vinegar and such on their hair, but there has to be a limit to how low the pH can get before it begins to dissolve hair, right? How low is too low?

Why worry about it? Just use a small dollop of vinegar in a 1L bottle of water.... don't use undiluted vinegar.

Knifegill
September 13th, 2014, 02:10 AM
That's awesome, and practical, advice. I was just curious about the science, where hair begins to suffer instead of benefit.

Dreams_in_Pink
September 13th, 2014, 04:06 AM
The first time i applied henna, i prepared the mixture with 5 lemon's juices. I let the paste sit for 6 hours. My hair was fried and i had dandruff problem for 6 months straight. So yes, you need to be careful with acidic stuff :)

sarahthegemini
September 13th, 2014, 05:42 AM
Interesting question. I've not thought of that before. Eagerly waiting for answers...

MsPharaohMoan
September 13th, 2014, 06:47 AM
if only there was a longhair somewhere out there with a microscope and a lemon…

Caraid♫
September 13th, 2014, 07:42 AM
The first time i applied henna, i prepared the mixture with 5 lemon's juices. I let the paste sit for 6 hours. My hair was fried and i had dandruff problem for 6 months straight. So yes, you need to be careful with acidic stuff :)

yikes!! :blueeek: that's awful that that happened, but it's a good cautionary tale for the rest of us!!

Dreams_in_Pink
September 13th, 2014, 10:04 AM
yikes!! :blueeek: that's awful that that happened, but it's a good cautionary tale for the rest of us!!

I keep warning people about that. I think acid is only necessary if something very alkaline (like baking soda) is used prior to acid. That's when pH levels are balanced, making hair feel smoother. Other than that, not necessary IMO.

Marika
September 13th, 2014, 11:04 AM
Long time ago, I used a (now discontinued) Redken product with pH of 3.5. My very bleached and damaged hair loved it. Redken Extreme line really saved my hair back then. No idea, what is too acidic but 3.5 was perfectly fine. Having said that, I didn't exactly check the pH level myself in any way, just trusted what the bottle said.

ETA: pH 4.5-5.5 is supposed to be the ideal pH level for skin and hair.

GetMeToWaist
September 13th, 2014, 11:45 AM
I just... Wouldn't use ACV or lemonjuice. Can't see the benefit of rinsing hair in something acidic.

Platzhalter
September 13th, 2014, 11:59 AM
It probably also depends on the reason for you to use an acidic rinse. Those who do it because they live in an area with extremely hard water usually need to make a "stronger" rinse than those who don't.

Entangled
September 13th, 2014, 12:00 PM
Acid can be just as damaging as any chemical. Just because things are natural doesn't mean they're safe!
I still love my white vinegar rinses, though. They make my hair so smooth, shiny, and soft! I do dilute quite a bit to make sure it's not damaging.

meteor
September 13th, 2014, 02:38 PM
Obviously, everything water-based that we eat or put on our skin or hair has some ph, and it's important to be mindful of that.
Something with ph of 6 is acidic, but it might be too "alkaline" compared to hair's ideal ph state, which is why almost all commercial hair products have some ph-adjusting ingredients added to them (often it's citric acid).


I keep warning people about that. I think acid is only necessary if something very alkaline (like baking soda) is used prior to acid. That's when pH levels are balanced, making hair feel smoother. Other than that, not necessary IMO.

I agree with this!


Long time ago, I used a (now discontinued) Redken product with pH of 3.5. My very bleached and damaged hair loved it. Redken Extreme line really saved my hair back then. No idea, what is too acidic but 3.5 was perfectly fine. Having said that, I didn't exactly check the pH level myself in any way, just trusted what the bottle said.

ETA: pH 4.5-5.5 is supposed to be the ideal pH level for skin and hair.

Yes, bleached and damaged hair likes more acidic environments, which is why products (esp. conditioners) for chemically processed hair tend to be more acidic. :)

I highly recommend Natural Haven Bloom's blog articles on ph and hair:
http://www.thenaturalhavenbloom.com/2009/04/blog-experiment-ph-and-your-hair.html
Ph of common shampoos: http://www.thenaturalhavenbloom.com/2012/02/ph-of-shampoo-ultimate-list.html
Ph of common conditioners: http://www.thenaturalhavenbloom.com/2012/02/ph-of-conditioners.html
Ph of common leave-ins and styling aids: http://www.thenaturalhavenbloom.com/2012/03/ph-of-leave-in-conditioners-and-styling.html

Beborani
September 13th, 2014, 03:10 PM
Short answer. Acids are categorised as weak and strong. Acids discussed on these boards is weak which means that their acidity do not change much with concentration compared to strong acids, so you cant overdo it to burn off your hair as you would say with concentrated nitric acid or sulfuric acid. That said, their pH does change enough that it is preferable to use dilute acids.

ExpectoPatronum
September 13th, 2014, 03:20 PM
I think you'd be fine with diluted vinegar or lemon juice.

I wouldn't go dumping hydrochloric or nitric acid on my scalp, however....

Sarahlabyrinth
September 13th, 2014, 03:53 PM
I would prefer to not use vinegar but we have very hard water here and I heard that it helps with that, so that's why I use diluted vinegar. I also dye my hair (roots only to minimise damage and on oiled hair), so hopefully I am keeping my hair as healthy as I can, considering that I do use dye.

jeanniet
September 13th, 2014, 03:59 PM
I think you'd be fine with diluted vinegar or lemon juice.

I wouldn't go dumping hydrochloric or nitric acid on my scalp, however....

This. If it's strong enough to actually dissolve hair (as opposed to just really drying it out), it would be seriously damaging to skin, eyes, etc. A dilute acid rinse is entirely different. Straight vinegar is a dilute acid mix (5%, generally), even without further diluting, but still too strong for hair as is.

cathair
September 13th, 2014, 04:31 PM
I've wondered this. I was measuring the PH of everything I was using. But it started to seem a bit pointless because I believe the PH scale goes up in factors on 10? So jumping from one number to next is actually a massive difference. So I'm not sure testing with PH paper is useful at telling you much unless a product is waaay out of the range of acceptable which is very unlikely.

I suppose it's more useful for testing vinegar rinses, but even then, it's not amazingly easy to tell the difference between the reddish colours the paper produce, if your not very experienced at that. Also I am not 100% sure if the idea of a vinegar rinse is supposed to be more acidic than hair, because it is trying to counter the any alkaline effects of water that the hair is saturated with. Or if it is intended to be the same PH as hair. My water seems to be on the alkaline side.

Beborani
September 13th, 2014, 05:23 PM
Ok a bit more. Here is a quick reference. Vinegar sold in shops is about 1M. It will not hurt you even if you do full strength rinse accidentally but it is more economical not to mention less stinky to dilute it at least 10 times and even 100 times is sufficient if you just want acidic rinse or even leave in. As someone upthread mentioned if you have hard water you may want or play with dilution a bit to make sure you get most of the metal ions--I prefer citric acid for this as it gets more metal ions than acetic acid (vinegar).

0.1 M acetic acid = pH 2.87
0.01 M acetic acid = pH 3.37
0.001 M acetic acid = pH 3.8
0.0001 M acetic acid = pH 4.3
0.00001 M acetic acid = pH
Vinegar is ~5% acetic acid solution which is ~0.9 M which is ~pH 2.4

ravenreed
September 13th, 2014, 06:22 PM
I use a diluted ACV rinse with every wash. My water is incredibly hard here and it not only helps with that, but it also keeps my scalp happy. I have tried lemon juice, but it isn't as effective for my scalp.