One Product. Every Hair Type. Here's the Data.

A few years after we founded Hairstory, two new companies arrived with enormous fanfare and a simple, seductive premise: your hair is unique, so your shampoo should be too. Function of Beauty and Prose swept into the industry promising fully customized formulations — push you through a detailed quiz, analyze your specific needs, ship you a bottle with your name printed on it. Investors loved it. The press loved it. Between them, they raised something in the neighborhood of a hundred million dollars.

I watched all of this with a particular kind of frustration. Because from the moment I read their pitch decks, I was pretty sure both businesses would fail. And I couldn't say so to anyone who would listen.

Here's what I believed then and still believe now. There were two fatal flaws baked into the model.

The first was the consumer promise. Both companies pushed prospective customers through extensive, highly detailed intake quizzes — hair type, porosity, goals, lifestyle, climate — and pledged that the resulting formula would be calibrated precisely to their needs. As someone who had spent years inside this industry, I had a strong suspicion about what was actually happening behind the curtain: a handful of slightly different base formulations, with small quantities of additives mixed in to support the customization claim. The analogy I kept coming back to was Jamba Juice. You pick your smoothie, you pick your add-ins, and you feel like you made something personal. But the base is the base. The magic is mostly in the presentation.

The second flaw was operational. Even if you're working from common base formulas, the process of individualizing each bottle adds significant friction to every step of production. No co-manufacturer or contract packager will take that on at scale. So these companies had to build and operate their own production facilities — a capital-intensive, complexity-multiplying commitment that was always going to make profitable scaling exceptionally difficult.

Neither of these problems showed up in their sales numbers early on, because they were doing something clever: buying sales. Spending heavily on digital marketing to acquire customers at costs that were never going to be sustainable, growing the top line fast enough that someone — a strategic acquirer, a later-stage investor — might be impressed enough to get them out. The greater sucker theory of business building.

Meanwhile, we were bootstrapping Hairstory. Growing slowly. Earning customers. I watched Function and Prose sail right past us in fundraising, in press coverage, in apparent valuation, in everything that looks like success from the outside.

It was frustrating. But I kept believing we were building something they weren't: a business that actually delivered on its promise.

The thing I couldn't stop thinking about

Here's the irony that made all of this so maddening. While Function of Beauty and Prose were selling the idea of customization — and, in my view, not quite delivering on it — Hairstory had something that actually worked differently for every single person who used it. Without any customization at all.

The hair industry has spent decades convincing you that your hair has specific, particular needs that require specific, particular products. Shampoo for dry hair. Shampoo for oily hair. Shampoo for color-treated hair. Then conditioner to restore what the shampoo stripped. Then styling products to add back the texture the conditioner smoothed away. A scalp serum. A curl cream. A frizz-control oil. The product count grows every year because the category is built on a premise that requires it: shampoo disrupts your hair, and you need an expanding arsenal of products to compensate.

Hairstory was founded on the opposite premise. We called it "less is more," but the real philosophy is simpler than that: fix the root cause and you don't need most of the other stuff.

The root cause is shampoo. As I wrote in the dandruff article — and as I've come to believe more firmly the longer I've been in this business — the foaming detergent in every shampoo, regardless of how gentle it claims to be, strips away your scalp's natural protective oil barrier and washes away your microbiome. Your body responds by going into overdrive to replace what was lost. Overactive oil glands. Exposed skin. A disrupted microbial balance that, in many cases, gets colonized by the wrong organisms. The result is a stressed, irritated scalp — and hair that never quite feels or looks the way it did when you were a kid.

My simple rule: if it foams, it strips.

New Wash doesn't foam. It's a cleansing cream — oil-based amphiphilic molecules derived from essential oils and esters — that removes what you want removed without stripping away what your body needs to protect itself. As I've described before, some of those molecules don't fully rinse away. They attach to your hair as emollients, conditioning as they cleanse. The result, for your scalp, is the end of the vicious cycle: no stripping, no overproduction, no vacuum for invasive microorganisms to fill.

What happens when your scalp finally calms down? You get back to the hair you were always meant to have. Not the hair the industry has been managing for you — the hair your body produces when it's in balance. Many people describe it as feeling like their hair from twenty years ago. That's not a marketing claim. That's just what happens when you stop disrupting something that was working fine.

The same product. Wildly different benefits.

Here's the part that I still find remarkable, even after a decade: New Wash delivers something completely different to each person who uses it — and all of them love it, for entirely different reasons.

We didn't design it this way. It's just what happens when you stop stripping and start working with your hair instead of against it. The underlying biology is the same for everyone; the expression of healthy hair varies enormously depending on your hair type.

We have 25,513 New Wash reviews. I recently went through them segment by segment, and here's what they show.

Fine and thin hair is our largest cohort — 4,275 reviews, 82% positive, averaging 4.38 stars. The consistent theme is volume and body, not weight. People who spent years washing daily because their hair went flat by noon report washing every other day and actually preferring their hair. Fine hair doesn't need more moisture — it needs less disruption. New Wash gives it that.

Curly hair is our most enthusiastic segment — 3,060 reviews, 89% positive, averaging 4.61 stars. Curly hair is inherently more porous and more prone to moisture loss, which is why frizz is such a persistent problem. Shampoo makes it worse by stripping what little moisture protection curly hair has. New Wash restores it. People converting from the Curly Girl Method or DevaCurl tell us their curl definition improved, their frizz disappeared, and they simplified their entire routine.

Color-treated hair: 1,398 reviews, 88% positive, 4.57 stars. The mechanism here is straightforward — shampoo strips color along with everything else, so salon color that should last six weeks starts fading in three. New Wash removes the stripping without removing the color. Customers explicitly calculate the financial value: fewer salon visits, longer-lasting color, premium products they can finally stop buying. This is a commercially valuable segment that advocates loudly.

Grey and silver hair: 483 reviews, 91% positive, 4.66 stars. The highest satisfaction rate of any segment in our dataset. Grey hair tends to become wiry, coarse, and prone to yellowing — all symptoms of hair that's been chemically disrupted for decades. When the disruption stops, the texture improves, the brightness holds, and customers stop fighting their hair. We have multi-year repeat customers in this segment who describe New Wash as the first product that ever actually worked for them. This is a deeply underserved category that deserves far more attention than it gets.

Damaged and over-processed hair: 960 reviews, 88% positive, 4.53 stars. What's striking here is the competitive context. These reviewers are explicit about what they tried before — Olaplex, K18, Bumble and Bumble, Living Proof — and why it wasn't enough. They came to New Wash as a last resort. That makes their satisfaction rate one of the most credible signals in the entire dataset.

Wavy hair: 1,407 reviews, 87% positive, 4.52 stars. Many customers in this segment discover, after switching to New Wash, that their hair is wavier than they ever knew. Sulfates were masking it.

There is one segment that tells a more complicated story, and I think honesty requires including it: oily and greasy hair, at 1,517 reviews, has a 71% positive rate — the lowest in the dataset, with an 11% negative rate that's an outlier compared to everything else. The mechanism of New Wash relies on oils to cleanse; for people whose scalps already overproduce oil significantly, the "squeaky clean" sensation they're accustomed to doesn't arrive, and the adjustment period can feel worse before it gets better. This is part of why we developed Pre-Wash — a targeted treatment that pre-cleans the scalp and feeds the microbiome before you use New Wash. Expectation-setting matters here. New Wash works for most oily hair; it just works differently, and the path there requires some patience.

Personalization is not the same as customization

This is the distinction I could never get the industry to hear when Function and Prose were ascendant.

Customization says: your hair is different, so your formula must be different. It sounds compelling. It's also, I believe, largely theater.

Personalization says: your hair is different, so the way we talk to you about our product needs to be different. The formula is the same. The outcome — healthy, balanced hair — is the same. But the story we tell a fine-haired person is completely different from the story we tell someone with tight coily curls or grey hair or a decade of bleach damage.

A fine-haired person doesn't need to hear about moisture. She needs to hear about volume without weight. A curly-haired person doesn't need to hear about shine. She needs to hear about frizz and definition. A grey-haired person needs to hear about texture and brightness. None of these people are using a different product. They're all using New Wash. But if we tell the same story to all of them, we lose all of them.

This is harder to build than a quiz. It requires actually understanding what your product does across a range of different people — understanding it well enough to translate it accurately for each of them. It's an investment in knowledge, not in manufacturing complexity.

And it's sustainable.

It has now been more than five years since Function of Beauty and Prose raised their enormous rounds and lapped us on every metric that Wall Street cares about. What I hear about both businesses these days is not encouraging. Whether the pressures are structural or just the general difficulty of the moment, they seem to be struggling. I won't gloat about it — building any business is hard, and the people who tried deserve credit for trying.

But I do believe the underlying logic was wrong from the start. You don't win by manufacturing complexity. You win by understanding something true about your customer, and delivering on it, one person at a time.

We're still doing that. Slower than some, more honestly than most.

And the reviews are there if you want to read them.