Do You Need a Clarifying Shampoo?

Researched and written by Curl Centric. Read by an AI voice.

If your curls feel coated or look dull, buildup may be why. We'll explain what a clarifying shampoo does, how often to use it, what hard water has to do with it, and when it can leave your hair feeling worse.

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The full guide, with every source: How to Clarify Curly Hair at Home: DIY Clarifying Guide.

Our free wash day builder: https://www.curlcentric.com/wash-day-routine/

Transcript

This is Curl Science by Curl Centric.

If your curls have started to feel coated or look dull, you may have buildup. A clarifying shampoo is the usual fix. In this episode, we'll explain what clarifying shampoo does, who needs it, how often to use it, what hard water has to do with it, and when clarifying can make your hair feel worse.

Let's start with what it is. A clarifying shampoo is a deep-cleaning shampoo. It typically uses a strong cleanser, the same kind used in shampoos for oily hair. Its job is to remove what your regular wash leaves behind.

Mostly, that's styling product. Gels, hairsprays, and mousses can leave a thin film on your hair. A dermatology review explains that everyday shampoos aren't always good at removing that film. With daily styling-product use, it can build up after about a week and leave your hair feeling harsh and looking dull.

Gentle cleansing can add to it. If you co-wash, which means washing with conditioner, or only use very mild shampoos, residue can collect over time. A review of conditioner washing describes it as gentle on hair but notes that it can lead to buildup.

So how do you know you need to clarify? Your hair looks dull or feels harsh after a week or so of using styling products. Your curls feel coated, even after a wash. The American Academy of Dermatology adds one more clue. If you regularly style with gels, oils, creams, or pomades, it suggests using a clarifying shampoo before your moisturizing shampoo.

What about silicones? Some styling and conditioning ingredients build up more easily than others, but dimethicone doesn't necessarily keep stacking up with every use. A paper on two-in-one shampoo technology reports that each wash removes the dimethicone left behind by the one before. Buildup is more likely when you only co-wash or use very gentle cleansers.

Now, hard water. Hard water contains a lot of calcium and magnesium, and how hard yours is depends on where you live. Soap has a harder time lathering and cleaning in hard water, and old-fashioned bar soap can leave scum on your hair. Most modern shampoos are formulated to avoid that.

Do those minerals end up on your hair? Yes. Researchers examining hair under a microscope found more calcium and magnesium on strands soaked in hard water. Hair that's already damaged, including bleached or colored hair, also picks up more minerals than undamaged hair.

What those minerals do is less clear. In lab tests, they made strands stiffer, but they also made hair easier to comb. Researchers still disagree about whether hard water makes hair weaker. One study found no change in strength, while another found that straight hair soaked in hard water was about 8 percent weaker.

Copper has a clearer effect, and it can come from tap water or pool water. In lab studies, copper on the hair can speed up sun damage and add to the damage caused by permanent hair color. It can even turn light or bleached hair green.

That's where chelating shampoos come in. A chelating agent is an ingredient that grabs onto minerals. Many shampoos already contain one, such as EDTA, so the minerals in your wash water don't form a dull scum on your hair. If your water is hard or you swim frequently, a chelating shampoo can help limit mineral and copper buildup.

Before we get to how often, one quick ask. If you want more answers like this, follow the show, so the next one finds you.

So how often should you clarify? There's no single number. A Cleveland Clinic dermatologist suggests once or twice a month if you use a lot of styling products. One dermatology review suggests about once every ten washes, or more often when needed. For many women with curly hair, once or twice a month is a reasonable starting point, not a rule. Clarify more often if you use heavy gels and butters, and less often if your hair is already dry.

Here's when clarifying can make things worse. A strong cleanser doesn't only remove buildup. It also removes your hair's natural oil, and hair with no oil left feels harsh and looks dull. Strong cleansers leave more friction and static between your strands, which can make them easier to tangle and break. Follow a clarifying wash with a conditioner or hair mask that gives your curls plenty of slip.

Be extra careful with color. A dermatology review says heavily highlighted hair is especially sensitive to clarifying shampoos and may need clarifying less often, or not at all. Permanent hair color washes out a little with every shampoo, mostly because the dye dissolves in water. If your hair is colored or bleached, clarify only when you need to and use a shampoo made for color-treated hair between clarifying washes.

And a clarifying shampoo isn't a dandruff treatment. If your scalp is flaking and itching, look for a dandruff shampoo with an active ingredient such as zinc pyrithione or ketoconazole. We covered that in our dandruff episode.

Here's how to clarify. Wet your hair thoroughly. Put the clarifying shampoo on your scalp and work it through the parts of your hair where styling products collect. Rinse well. Then apply a conditioner or mask and leave it on for the amount of time listed in the directions. Detangle gently while the conditioner is still in because your hair may have less slip after a strong cleanser.

One more tip about pH. Many shampoos have a higher pH than your scalp, and alkaline products can raise the friction between your strands. A dermatology paper suggests following any shampoo above pH 5.5 with a low-pH, slightly acidic conditioner to help your hair feel smoother.

What about home remedies? Baking soda is alkaline, with a pH around 8. That's higher than both your scalp and hair, and alkaline products can raise the friction between your strands. We'd skip it. An apple cider vinegar rinse is acidic, but it isn't a shampoo, so don't count on it to remove product buildup.

So here's what we'd do. If your curls feel coated or look dull, start with a clarifying shampoo once or twice a month. Clarify more often if you use heavy styling products and less often if your hair is dry, colored, or bleached. If your water is hard or you swim, look for a chelating shampoo. Follow every clarifying wash with a slippery conditioner or hair mask.

Our full guide to clarifying curly hair is linked in the show notes, along with our free wash day builder. And if this helped, follow the show for the next one.

That's it for this episode. If it helped, follow Curl Science in your podcast app so the next one reaches you, and leave us a rating while you're there. Curl Science is researched and written by the Curl Centric team, and it's read by an AI voice.