What is a clarifying shampoo?
A clarifying shampoo is basically an intensive hair detox. Build-ups from hair products such as sprays, mousses, gels, oils or waxes – as well as from hard water, chemicals and pollution – can break down the structure of your hair over time, leaving it dull and lifeless. Clarifying shampoos are designed to strip out these residues, giving your hair a fresh start and restoring its shine and manageability. They are used on wet hair and should be distinguished from dry shampoos, which instantly absorb excess oil for short periods.
There are dozens of websites providing DIY clarifying shampoo recipes, many of which include baking soda and/or vinegar. Some even suggest that you can transform your regular shampoo into a clarifying shampoo by adding vinegar. We would always recommend a professional clarifying shampoo that has been specially formulated and tested to deliver results. Baking soda in particular should be used with caution as its high alkalinity can disrupt the pH of your scalp and damage the hair shaft.
When should you use a clarifying shampoo?
Warning signs that you might need to try a clarifying shampoo include: a reduced lather when you shampoo, your conditioner works less efficiently and your hair feels dry or excessively oily, you have a scaly film on your hair or an itchy, flaky scalp, your hair has less bounce and shine, it tangles more easily and is difficult to brush, it is less responsive to styling or your hair tools need to be hotter to produce the same results.
But don't just throw our your standard shampoo. As well as deep-cleaning your hair of build-up, clarifying shampoos can strip out your natural oils, which are necessary for good scalp and hair health, so ideally use one only when necessary.
As a general rule, a clarifying shampoo should be used fortnightly or monthly, depending on your hair type. This is particularly true if your hair is colour-treated (see below). Frequent swimmers or those using a lot of styling products or particularly hard water may find they need to clarify weekly, while those with hair prone to dryness (like naturally curly or textured hair) may find it necessary only a handful of times throughout the year.
Are there any downsides to using a clarifying shampoo?
As mentioned, clarifying shampoos can strip out natural oils, but ironically their overuse can exacerbate an oily scalp – your oil glands effectively work overtime to combat the excessive dryness. This greasiness can then trick you into using clarifying shampoo even more frequently in a downward spiral.
There is also a risk that clarifying shampoos can exacerbate skin conditions, particularly if they contain sulphate-based cleaning agents. If you are prone to dandruff, seborrheic dermatitis, eczema or psoriasis, look for a sulphate-free clarifying shampoo and use with caution.
Can you use a clarifying shampoo on coloured or permed hair?
Not all clarifying shampoos are colour safe so read the label thoroughly, but in general they can be used on coloured or permed hair.
Clarifying can actually brighten your tone by clearing out residues that dim your colour. For blondes in particular, clarifying shampoos can remove mineral deposits that may turn your hair brassy and yellow (we would recommend following up with a purple shampoo to tone it). For swimmers, it can also help to eliminate any green tint resulting from chlorine exposure. However, since clarifying shampoos can also strip out colour, we would suggest avoiding for at least a week after you have fresh colour applied and not using too frequently. If you have coloured your hair a vivid hue, gone from blonde to dark or corrected your colour, it may be best to avoid altogether, but ask your stylist for advice.
Clarifying shampoo can be most beneficial before a new colour service. When you’re preparing to colour, add highlights or low lights, or apply other chemical treatments, it can help to remove oils or products coating the cuticle that may interfere with the treatments, allowing the colour to deposit more evenly along the hair shaft. In addition, post-colour, where your resulting colour or hue is much darker than desired, your colourist may actually recommend trying a clarifying shampoo to remove excess colour.
Clarifying prior to a perm can also enable the solution to penetrate the hair better. However, as with colour, we recommend that you hold off from using a clarifying shampoo for a week after treatment, and ensure your perm is properly hydrated on mid lengths and ends with a good conditioner and serum.
Can you use clarifying shampoo on hair extensions?
Since extensions are not attached to your scalp, your natural oils (sebum) do not travel down the hair shaft to moisturise it. Clarifying shampoos can be used to remove product residue and bacteria from your extensions, giving them a new lease of life.
Prior to installation, you can also use clarifying shampoo to clean the hair and provide a strong bond. This is particularly true for tape-in extensions to help you remove any conditioning agents that could cause slippage.
How do you use a clarifying shampoo?
Using a clarifying shampoo is no different than other shampoos, but you may need longer in the shower to really reap the rewards. Ensure your hair is completely wet, and then start by massaging the shampoo into your roots where residue tends to accumulate. You can then progressively work this down through the length of your hair. Your hair is at its most fragile when wet, so avoid rubbing or scrubbing during the application. Let the shampoo sit on your head for a couple of minutes to release the product build-up, before rinsing thoroughly. If your hair has been particularly troublesome and dryness is not an issue for you, this step can be repeated. Then apply a deep condition or hair mask, working it in from mid-shaft to ends, to restore any lost moisture.
Everyone responds differently to clarifying shampoo, so listen to your hair. If you think that a clarifying shampoo may be too harsh for your hair type or texture, you could try diluting it – for example, three parts water to one part shampoo – in a separate container before applying to your hair. But if you have any real concerns, we would always recommend that you discuss your hair needs with your trusted hair professional.
Which ingredients should you consider?
Many clarifying shampoos contain harsher cleansing agents or surfactants such as sodium lauryl sulphate(also known as SLS) or sodium laureth sulphate, which work by attracting dirt and oil molecules alongside water molecules. Without a surfactant, dirt and oil do not mix with the water and are left behind on the hair. While you should avoid surfactants in your daily shampoos, they should be fine to use infrequently for clarifying purposes. However, if you prefer to avoid SLS and other sulphates, you can find shampoos with gentler non-sulphate surfactant cleansers such as cocamidopropyl betaine (note that these won't produce the same rich lather though).
Clarifying shampoos also use chelating agents such as EDTA, which bonds with metal ions in water so that it is softer on your hair. They generally also include acetic acid (the main ingredient in vinegar) or citric acid (found naturally in citrus fruits such as lemons and limes), which work to remove mineral and chemical deposits in your hair. Many also contain purifying ingredients to soothe your scalp and remove impurities. These include: tea tree or eucalyptus, which have anti-inflammatory and anti-bacterial properties to stimulate the scalp; witch hazel to reduce scalp sensitivity and remove excess oil; willow bark to exfoliate your scalp and unblock hair follicles; and sage, rosemary, ginseng or peppermint to improve circulation and stimulate hair growth.
Clarifying shampoo formulas are often clear rather than creamy. They shouldn't contain conditioning agents such as dimethicone, as they are intended to remove residue rather than deposit more.