Hair is a fascinating subject.
For example, did you know a single strand of hair normally has a lifespan of about 6 years? Or that it grows, on average, about 14 centimetres every calendar year? Or that one strand of hair is remarkably strong and when healthy, can carry a weight of up to 100 grams? Probably not. You may already know that hair loves a protein treatment. But what you many not know is that it equally loves, loves, loves an acidic based rinse or treatment. So much so, that we think that an acid rinse is arguably just as important a step as protein for the overall health and maintenance of the hair. Why? It has to do with some hair fundamentals involving the hair's cuticle, it's preferred pH and a few negatively charged ions.
Let us explain.
Charged up
Perhaps the first thing to understand about your hair is that on the surface it carries a charge- a negative charge to be precise. In healthy hair, these negatively charged groups are mild, mostly limited to the surface of the hair and are not much cause for concern. You have likely already experienced the 'negativity' of your hair, particularly in those cold and dry winter months when the forces of nature all align to make your hair rise and stand on end for no apparent reason. That is the result of the positive ions in the air coming together with the negative ions on your hair, often to spectacular effect. The problem is not the negative charge itself, but when the hair carries an excessive negative charge, too many, in other words.
But how and why does that happen? As a general rule, hair that is damaged has a greater negative charge than healthy hair. Excessive sun exposure, chemical processing or heat styling will all result in giving the hair a more net negative charge. Fine, you say, so the charge of my hair is overwhelmingly negative. Why should I care? You should care because it is in this negatively charged state the hair becomes a like a magnet for the positive charges that come from washing our hair with municipal tap water and the negative charges in our shampoo. Layers of build up that lead to a vicious hair cycle as you will soon learn.
Hard water
Municipal water has its issues for sure- traces of pharmaceuticals, chlorine, fluoride.... the list goes on and on. Toxic contaminants aside, the argument against using tap and investing in a good shower filter is made all the more convincing when one learns the effect it has on our hair over time. The problem with tap lies in it's generally calcareous nature and strong positive charge. Calcareous meaning that it is high in both Calcium and Magnesium, and not the good kind either. The version of these that is found in our water carry a positive charge and have a strong attraction to the negative surface charge of our hair. These 'hard' minerals as they are called, bind to the cuticle directly and make even the healthiest strands feel stiff, dry and enormously prone to tangle. The more damaged the hair, the more of these minerals deposits you will likely have and the more dry and unmanageable your hair will be. Oh, and it also works to distort, fade and alter many natural and salon colors, especially blondes.
But it gets worse.
Enter shampoo
We already know that the use of conventional, especially sulphate (sulfate) containing shampoos presents a whole set of problems for the hair and scalp microbiome- everything from chronic dryness, to damaged or weakened follicles and lacklustre or even arrested hair growth. But to make matters worse is the discovery that most surfactants or soaps (even natural ones) carry a negative charge and therefore-you guessed it- have a tremendous tendency to cling to the said positive charges in the hair cuticle.
This small but important insight helps to explain why for so many, the hair so often looks and feels a dull, heavy and tangled mess even after shampoo and conditioner.
This unholy combination of hard water mineral build up and lingering soap residues (made even worse if your hair is already damaged) means that we have these perpetual layers of unwanted build up that just kind of stays there, no matter what we do. If you are thinking you should be able to just 'wash it all off with a good shampoo', forget about it- shampoo is often part of the problem. As an aside, we can't help but think that maybe this is why 'hair and scalp oiling' is trending at the moment. The idea seems born out of sheer frustration with our chronically dry hair and scalp; the perception that if we just keep replenishing and adding to our own natural oils -perpetually 'coating' it- that many of our hair problems (and dryness) can just go away. Maybe so. But while these methods can perhaps help to mitigate the problem and temporarily make the hair feel and appear softer the reality is until we remove the built up mineral and soap residues, the hair will suffer.
The pH problem
We so often hear about the importance of 'restoring the hair's pH' or 'pH balance' of the hair. But exactly what does this mean? The 'potential of hydrogen' or pH is the acid to alkaline scale that most of us studied in high school. It is used to measure just how acid or alkaline a substance or object is. The pH of the hair and scalp sits anywhere from 4.5 to 5.5 on the scale of 1 to 14, where 1 is very acidic, 14 is very alkaline and 7 is neutral. When the hair and particularly the scalp gets out of its preferred range, many problems, some of them chronic, can soon follow.
For most of us, it is rarely the case that the pH of our hair and scalp stays within range. It is most often the case that the scalp is more alkaline (above 6.5 or 7) instead of the slightly acidic pH that is its preference. This is due to many factors, the two most common being once again our water supply and the products that we use. A raised pH means that the scalp's natural barrier (microbiome) cannot function optimally, especially with regards to its production of sebum- the natural oils and lipids that we produce to protect us from threats such as dandruff, dryness, inflammation, certain bacteria and even infections. What they fail to tell you is that a scalp that tends towards an alkaline pH is typically dry, irritated, itchy and not able to self regulate.
What does an alkaline pH do to the hair itself? It's not pretty.
The cuticle is the hair's outermost layer of protein that is visible to the naked eye. If you look at a healthy cuticle under a microscope it resembles interlocking scales or shields that together form a smooth, closed surface. Think of a pine cone with the scales closed. It appears smooth, shiny and its scales reflect the light.
The cuticle is your hair's first line of defence and is there to protect the innermost part of the hair called the cortex. In order for the cuticle to look and be healthy, it needs two conditions to be met: one, it's protein layer needs to be kept intact and it's thickness maintained and two, its individual scales need to lie flat and be tightly shut so that the cortex of the hair is protected (nothing coming in or out). The ideal situation where the cuticle is completely sealed and closed is rare thing indeed. By far most of us are walking around with a cuticle layer that is raised, lifted and more or less open. Why is this? Heat styling and chemical applications do their fair share of damage, eroding the thickness of the cuticle layer, and are the reason why regular protein treatments are so important.
But even if you don't use heat or color your hair, your cuticle is still likely to be raised or opened due to (once again) our use of city tap water and shampoos. Let us explain. Municipal tap is generally speaking more alkaline (between 6.5 and 8.5) and the harder the water, the more alkaline it is. Adding to this is that most conventional shampoos are more alkaline, with some even as high as 9 (!) on the pH scale. In the end it is the pH of the water that prevails and will likely bring the overall pH down somewhat but not nearly enough to ensure a closed cuticle. So our cuticle for the most part remains open or partially so and just like the pine cone with the opened scales, our hair is dried out and tangles easily, with little to no lustre, sheen or shine, the individual scales catching on each other like velcro. No wonder we are always reaching for the silicone stylers, finishers or oils. What else can we do?
The acid rinse
Excessive ionic charges, hard water and product buildup, a malfunctioning scalp microbiome, an alkaline pH and a miserable, opened cuticle is why the hair and scalp LOVES and is often desperately in need of clarification via an acid rinse.
An acid rinse, treatment or tonic is typically made of weaker, natural acids such as acetic, malic or citric drawn from natural sources such as apple cider vinegar, kombucha, lemon juice and even some clays.
These acids do two very important things.
First, the acids neutralize the extra charges and allow the hard minerals and soap residues buried in them to be lifted and washed away, in a way that most shampoo can do. This makes the hair and scalp breathe a sigh of relief as it is made almost instantly lighter and free of debris and heaviness. Secondly, the lower acidity of an acid rinse (4.5-5) causes the individual scales of the cuticle to contract, close, and lie flat and smooth. The hair is at once smooth and shiny as it can again reflect the light. Another happy effect of doing an acid rinse is how incredibly softening it is to the hair. These deep conditioning properties, where the the hair is left feeling so soft and moisturized is largely because the hair has been rid of its heavy mineral and product coating and in doing so a clarifying acid treatment acts very much in some ways like a deep conditioning treatment- but without the heaviness that too many conditioning products can often cause.
How often should one do an acidic clarifying treatment you ask? As often as you need, but particularly in the case where you hair feels stuck- like your regular routine of shampoo and conditioner, even hair mask is not working. Also, if your hair feels stiff and has little softness no matter how many products you throw at it, its time for an acid rinse.
Try it and be amazed at the results.
-HT
