Hair Health Starts With the Scalp


Hair care scientists scratched their heads for some time before they could put their finger on the primary causes of dandruff. Now, with the flakes brushed away, they are seeing the scalp in a new light—which is bringing new insight on factors affecting hair’s condition, as well as new capabilities to match shifting consumer expectations.

Two Procter & Gamble scientists, James Schwartz, Ph.D., and Rolanda Wilkerson, Ph.D., both with the Head & Shoulders brand, explain how in this exclusive interview. (To view the video series, see Video 1, Video 2, Video 3 and Video 4.)

C&T: What new benefits do consumers want in hair care? What’s changed and why?

Schwartz: No one wants flakes; everyone understands that. But recently, there’s a new understanding that if you have an unhealthy scalp, the hair that grows from it is also unhealthy. We believe that people’s expectations are changing in such a way that, in addition to the apparent benefits of reducing flakes and itch from a scalp care shampoo, they’re also starting to expect hair benefits. And not superficial, cosmetic hair benefits—real benefits because you are actually now able to grow healthier hair. We’ve started to put a lot of understanding to why that is the case.

An unhealthy scalp is a lot more than superficial flakes and itch. In fact, any molecular or functional measurement you can make of an unhealthy scalp will be irregular in a dandruff sufferer versus not. Hair grows from the place it is “born” in the scalp, about 4 mm deep, and takes about two weeks to get all the way to the scalp surface. So during that two-week period, it’s being “bathed,” if you will, by the surrounding scalp tissue. If the surrounding scalp tissue is unhealthy, it’s affecting the quality of that fiber as it starts to form. We find that when the new hair emerges from the scalp, in dander sufferers, it’s already compromised in its structural integrity.

Then it has two years or so, with longer hair, for example, to be exposed to the environment. So it’s already starting out compromised, and it becomes more susceptible to all the environmental stresses it experiences. So we see the link between scalp and hair condition is very strong, and that benefit space is becoming important to scalp care shampoos, like Head & Shoulders.

Wilkerson: Just to build on that, consumers understand that healthy hair leads to beautiful hair. As a part of that, they’re also looking for products that provide really excellent “cosmeticity” in terms of the fragrance of the product, how the product feels, the lather and how it makes the hair feel. Those are the acute benefits.

Then, over time, they’re also looking for chronic benefits to show that the product’s actually working. So in the case of Head & Shoulders, it’s hair health as well as reduced flaking, moisturizing the scalp, and reducing dryness and itch.

"We believe that people’s expectations are changing in such a way that, in addition to the apparent benefits of reducing flakes and itch from a scalp care shampoo, they’re also starting to expect hair benefits."

How can products based on the same active(s) provide different efficacy?

Schwartz: We find it’s a common assumption that our products provide the same benefits in the same way to the same magnitude. In fact, if one looks on the back of the bottle, they would most commonly see the active labeled as 1% pyrithione zinc. While this [active level is] true, it is in a complex delivery vehicle, like a shampoo, and there are an awful lot of factors that determine to what magnitude of benefit the active will actually work.

So while the intent of the product is to primarily reduce the population of the commensal organism Malassezia—so that it’s not causing these problems of scalp health—and resolving hair heath, how effectively that product works depends on a number of variables associated with how it’s formulated. So the assumption that all products work equivalently we know to be untrue.

C&T: How do claims, efficacy and sensory testing enter the scene for anti-dandruff shampoos?

Schwartz: We do claims testing to support both cosmetic as well as efficacy performance. [In terms of] efficacy, double-blind, placebo-controlled studies are performed in which the primary metric is the amount of flakes on a person’s scalp. We have expert graders who assess the amount of flakes on a person’s scalp before and after treatment to make sure the product is reducing flakes. And not just doing it from baseline, but doing it differently than how a control cosmetic shampoo might.

These studies are done with large bases of people, often 500, and frequently we’ll publish the results. We treat these studies with the same diligence as a heart medication manufacturer would for their benefit space. You might argue it’s over the top, but it’s not. We’re very careful to make sure the product is always delivering the benefit that we promise.

Wilkerson: And we’ve been able to show through our clinical studies that Head & Shoulders products are actually providing superior efficacy versus some of the other competitive products that may even have two actives in a product. Being the No. 1 [anti-dandruff] shampoo in the world, we haven’t gotten here by chance.

C&T: What do you think consumers will want next?

Schwartz: Our expectation is that consumers will look for more hair care benefits from their scalp care products. There’s an appreciation globally that, much like soil is important to grow healthy trees, the scalp is important for growing healthy hair. People make that association already. Our expectation is that more consumers will start to appreciate that, “Gee, I really want to have a healthy scalp to make sure I’m always growing healthy hair.” And we think they’ll start doing that in a more proactive way. Not waiting for a problem or treating a problem then forgetting about it, but something they do as a part of a normal regimen to make sure they’re always giving their hair the best opportunity to grow.

"[Hair is under oxidative stress] and then the answer to this is having new product forms to deliver on the differing habits and practices of consumers."

Wilkerson: Another big trend we’re seeing is [immediacy of] results. Everything today is “I need it now, and I want it to work really fast.” Consumers are looking for signals in the product that it’s actually working for them, in addition to having, as I mentioned earlier, those chronic benefits as well.

C&T: What new technologies or scientific findings are you excited about?

Schwartz: One [finding] we’re really excited about and recently got into is an appreciation for the importance of oxidative damage in both scalp and hair health. We know a lot of things that are going wrong in the scalp of an unhealthy person. We know that histamine is released and there are inflammatory biomarkers. But what we learned recently is that in an unhealthy scalp, the oxidative stress level is way up.

Why is oxidative stress important? Oxidative stress is essentially like aging. A major theory of why we age is that we accumulate more and more oxidative stress. So when you have oxidative stress in your scalp, it’s like premature aging. The important thing about it is, at least as we’ve seen in the scalp, it can be reversed. So as long as you take care of your scalp, you can bring the oxidative stress level back down to the level that it was. And as we talked about scalp and hair condition before, when the scalp is under oxidative stress, unfortunately it transmits that oxidative stress to the hair before it’s formed. So that’s very exciting for us.

Wilkerson: And then the answer to this is having new product forms to deliver on the differing habits and practices of consumers. So for example, we recently launched a conditioner wash to really speak to differing consumer habits and practices. So as Jim mentioned, looking at oxidative damage and improving that factor, we have different products in different forms that will enable that.

C&T: What are you seeing in dermatology that relates to your work?

Schwartz: There’s a lot of discussion related to itch: both in products for treating itch and in new capabilities for measuring itch. This is really important because as we talk about primary symptoms for scalp health sufferers, flakes and itch are a big part of it. But as I mentioned, when we do our double-blind, placebo-controlled studies, our primary metric is actually flakes.

Itch is just as important, some would argue more important, it’s just very, very difficult to objectively quantify it. I’m starting to get the feel there’s going to be some much better opportunities to do some work around it.

Wilkerson: Another conversation is around normalizing scalp conditions. Over time, we’ve looked at dandruff as being taboo but a lot of talk, even with psoriasis or eczema, is that these are very normal conditions and a lot of people experience them. So we [need to] continue to have a conversation that says, for example, 50% of people in the world actually suffer from dandruff. It’s about normalizing that and really letting consumers know what they’re experiencing isn’t something isolated to them; it’s actually a normal condition.

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