But in order to talk about clean hair and overall hair happiness, we have to get dirty first. 

We put our hair through a lot. Bleach, chemical services, heat styling. We also put a lot on our hair. Products that throw our pH off balance, hard water exposure, oils, silicones, soft water, metals, minerals. READ: A LOT OF THINGS.  So, when it comes time to change up our look with another service or we want to try a new style, your hair has a lot of roadblocks (gunk) sitting on it. 

The truth? With a clean base, hair color applies more vibrantly, treatments perform more effectively, and styling products work better. 

To help illustrate the amount of, um, stuff sitting on hair, we tapped detoxing expert and salon owner Sherry Cassel who has become known for her buildup bags. 

Gross. But cool, right? 

Depending on the type of buildup her client experiences, Sherry will use either a detox shampoo to clear excess product off strands and scalp or a chelator to attract and bind metal + mineral ions in the hair. She then collects all of that in the bags above. 

All the figures you’ll see in this Science Sunday are examples of Sherry’s super cool work to bring clean hair to all. 

Let’s talk about the things that impact clean hair and/or the reasons you may end up in Sherry’s chair. 

pH

As we learned in our pH deep dive, healthy hair has an optimal pH of 4.4-5.5. Now, this is a self-regulating range, meaning without any outside factors introduced, your hair environment has everything it needs to keep this range in check. Introducing something foreign (read: everything from product to water with a different pH) can potentially throw off that balance. 

In the optimal state, the hair + scalp environments can successfully balance things like moisture, sebum production, and barrier function, but an imbalance of pH can affect sebum + oil levels which causes detrimental scalp inflammation. This typically results in dryness, flaking, dandruff, or oily residue. And when that happens? We often try to solve with more product use—which is what contributes to throwing it out of whack in the first place. Uh oh. 

Take a look at this detox Sherry did on completely virgin hair. This person had major oil buildup that wasn’t coming from chemical or color issues. It was simply coming from excess oils. 

product buildup

Speaking of excess, let’s talk product. Excessive product use can clog follicles and prevent healthy hair growth. Blockage from product at the scalp can also lead to scalp inflammation. 

When too much product has accumulated on your hair, the products you use are less effective because they don’t have a clear path to reach the hair and work where they are supposed to. Already saturated and weighed down by buildup, your hair can appear greasy, lifeless, and dull. 

Imagine continuing to add layers of clothes on top of the stuff you’re already wearing, without washing the under layers. We don’t do that to our bodies so why would we want to do it to our hair?

mineral + metals 

Now, we hate to say it, but every time you clean your hair, you are exposing it to potential buildup. Hard or soft water (depending on your location and water source) can contain minerals that will not only deposit onto hair but can react with other products used, forming a salt that creates even more buildup on scalp.

Hard water results from high concentrations of dissolved minerals, specifically calcium and magnesium. In some places, water can also contain varying amounts of copper, iron, nickel, and other metals that can wreak havoc on hair over time. 

Mineral buildup on your hair can weigh it down or lead to roughness, discoloration, and lack of shine. The buildup of heavy metals in your hair can induce damage that could distort its natural texture, making it feel straw-like and brittle. It can also weigh down or elongate curls, stretching them out and causing them to be limp or fall flat.

Even worse, attempting to color hair that contains certain metal ions, including copper, can cause the coloring process to go awry. The science? Metals accelerate oxidative reactions, i.e. what’s happening in a bleach or color service, which can lead to extra unintentional damage to hair proteins or uneven color. Then your colorist must work harder to get a consistent result—and you may not end up with the look you were hoping for.