Critically Reviewed by Sophie Davies, American Board Certified Haircolorist
For most of us, “shampoo” brings to mind a bottle of sudsy liquid with minimal nutrients and maximum viscosity; mostly water, but always laced with the obligatory “super-enriching” additives and an adult version of bubble bath (yes, we’ll talk about that), as well as a few ounces of various chemicals, not all of them bad for you, but not enough of them good for you either, thus a sprouting organic shampoo market worth an annual $1.1-billion dollars.
In 1988, in the United Kingdom, Lush co-founder Mo Constantine and cosmetic chemist Stan Krysztal walked shampoo into a bar, in a formula that became so successful and popular they patented it. In the three decades since, the field has exploded with a line of mostly better-for-you bars, and all of them from budding brands. (For the record, bars of palm fruit and coconut oil were used in the 30s and 40s for hair washing, so shampoo bars actually predate liquid shampoo.)
But anyway, here we take an unbiased look at what shampoo bars have blossomed into and how well they hold up against their modern liquid counterparts, beginning with the hopefully obvious: The first and most prevalent ingredient listed in any shampoo is water.
Does it make sense to be paying a premium for aqua (Spanish) or l’eau (French) to use in your already wet hair, while standing in a shower of running water? Methinks not.
Cons of a Shampoo Bar
As I ultimately believe shampoo bars have more pros than cons, we’ll start with listing out those few downsides, many of which you’ll see are shared with liquid shampoos.
- Shampoo bars are typically made of more natural ingredients and without preservatives so they have a shorter shelf life, usually of about 6 months.
- Users can expect an adjustment period and may have to shop around to find a personal favorite. It may also take a bit longer to start seeing results.
- Shampoo bars haven’t yet been made for specific hair types
- Users with long or curly hair may find lathering and applying them to be a bit of an ordeal, as most shampoo bars don’t contain SLS and SLES—the adult bubble baths we spoke of earlier.
- In hard water showers, shampoo bars might not perform as well as expected. Hard water is water with a high mineral content—if you find white scaling on your faucets or soap scum on your sink and tub, you likely have hard water.
- Some shampoo bars are sold with excited and exaggerated claims of their value, lifespan and results.
And that’s it. Those are the (quite relatable) cons and grudges we shampoo bars users most often share.
Pros of a Shampoo Bar
The pros, on the other hand, are numerous and convincing.
- Shampoo bars are generally made with more natural ingredients
- They are travel friendly: Compact, lightweight, and non-liquid.
- Shampoo bars are more cost effective
- Shampoo bars last three to five times as long as a bottle of liquid shampoo
- They are packaged plastic-free
- Shampoo bars have a greatly reduced carbon footprint
- They’re multipurpose and can be used for shaving, or clothes and body washing
- They leave hair very clean
- Most shampoo bars are free of SLS and SLES
- With shampoo bars, you don’t have to wash your hair as frequently.
What Is a Shampoo Bar?
Let’s get this out of the way: they aren’t bars of soap rebranded as shampoo. (Soap-based shampoo has a pH value too high for hair; you get static electricity, hair shaft and cuticle damage.) So, as the name implies, shampoo bars are the solid form of the liquid shampoo we’re all so used to. They are produced by concentrating cleaning and conditioning agents into a bar and removing all of the water. Those agents could just as easily be harmful or dubious chemicals, but because shampoo bars are manufactured by small companies that are focused on organic and all-natural product lines, and because they make these bars as a intentional contrast to the more common chemical-based liquid shampoos, shampoo bars tend to be a lot better for you and your hair.
Are Shampoo Bars Better Than Liquid Shampoo?
As their ingredients are more natural, shampoo bars are better than liquid shampoo. As with liquid shampoos, some searching may still be required, though because the space is new and filled mostly with those opting to offer an alternative to typically high chemical content shampoos, finding shampoo bars with no plastic bottles, no colorings, no fragrances, no palm oil, no SLS or SLES, no parabens, no cocamide, no DEA, and no silicones is extremely easy. (Here’s one.)
One of the strongest arguments for shampoo bars is their environmental appeal. More than 40 percent of all plastic used is in product packaging, including more than 80-billion plastic bottles that are disposed of globally each year—from shampoo and conditioner alone. Less than 10 percent of all plastic ever produced has been recycled and 8-million tons of it end up in our oceans yearly. According to studies, nine-tenths of fish have ingested microplastics and by the year 2050, it’s projected there will be more plastic in the sea than there will be fish. Shampoo bars help reverse and prevent that.
How Do You Use a Shampoo Bar?
This is the really hard part: Use it like a good ol’ regular bar of soap. Lather it between your hands to work up some naturally fragrant bubbles and slosh or massage those into your hair and scalp. If you’d like, you can also go ahead and place the bar directly on your hair and then start the whole lather-and-rub-around routine.
How Long Do Shampoo Bars Last?
Shampoo bars are considered to last from three to five times as long as their liquid counterpart. Storing them out of water’s way on a dry dish will extend their life. Of course, this is also going to vary from bar to bar, however it does hold that bars last longer. This conditioner bar by Ethique for example, claims it is equivalent to five bottles of liquid conditioner (and it doubles as a shaving bar and an inshower moisturizer).
Are Shampoo Bars Bad For Your Hair?
No. But just as with liquid shampoos, there are a few shampoo bars that are non-organic and filled with the same poor ingredients you might be trying to avoid. It’s best to check the ingredients and reviews of the particular bar you have in mind, but for the most part, shampoo bars are made by small businesses itching to bring you a product you’ll love.
Do Shampoo Bars Cause Hair Loss?
No. That allegation goes back to SLS and SLES (sodium lauryl sulfate and sodium laureth sulfate respectively), the two foaming agents most commonly used in liquid shampoos, the chemical structure of which vary by a single oxygen atom added during ethoxylation. As most shampoo bars specifically do not contain either SLS or SLES, the odds of them making your hair fall out are rather slim. You should, however, avoid shampoo bars with sulfates or SLS and SLES in them.
A quick history lesson, if I may, to set the record straight(er).
Steve Miller has jumped between being either a chemist or a company owner in the cosmetics industry for many decades. He worked at a reputable cosmetic company established more than 80 years ago that manufactured and packaged for 27 different companies.
In a 2014 lecture to cosmetologists, hairdressers and beauty school students, he shares the story of a client coming in to order a new shampoo. The gentleman says he doesn’t care if it cleans, he just wants it to lather. “I just want it to bubble.” Okay. So, nevermind if it even washes, the bubbles should be just fine?!
Oh, and breaking news for those who didn’t know: shampoos are actually detergent-based—yes, just like your dishwashing and laundry detergents. And the problem with that is that, unlike soap, detergents don’t lather naturally, they don’t bubble on their own. (Gasp!) Even stranger, shampoos don’t even need bubbles to do their job. The bubbles are chemical additives. And here’s where it gets interesting.
“One of the ingredients that we add to all detergents is bubble bath,” says Miller. “That’s when you look at the water being first, this detergent being second, and the third being a bubble bath…. But it’s ingredient number three. It’s a foam enhancer because detergents do not lather for crud [Miller used a different word but it isn’t quite SFW]. Well, we had to put the bubble bath in to make clients feel happy. Does it do anything for the hair? Not really. Does it help you clean? Uh, not really. Does it feel good? Kinda. Does it make the client think they’re doing something? You bet.”
Mr. Miller isn’t the only one to have shared this gem. The same customer feedback loop sales strategies have been applied to other cosmetics, including your mouth-tingling toothpaste.
Tracy Sinclair, a Procter and Gamble brand manager for 6 years who worked brands like Oral-B/Crest Kids toothpaste, told author Charles Duhigg (The Power of Habit), that consumers “need some kind of signal that a product is working.”
“We can make toothpaste taste like anything—blueberries, green tea—and as long as it has a cool tinge, people feel like their mouth is clean,” she says. “The tingling doesn’t make the toothpaste work any better. It just convinces people it’s doing the job.”
(In toothpaste it’s the tingle, in shampoo it’s the foaming bubbles.)
“Shampoo doesn’t have to foam,” Sinclair goes on to say, “but we add foaming chemicals because people expect it each time they wash their hair. Same thing with laundry detergent. And toothpaste—now every company adds sodium laureth sulfate to make toothpaste foam more. There’s no cleaning benefit, but people feel better when there’s a bunch of suds around their mouth. Once the customer starts expecting that foam, the habit starts growing.”
Why anyone would ever say that about a brand they managed is baffling, but since the book was published in 2014 and she moved on from P&G seven years earlier, that may have had something to do with it. (Hey, even Pasteur unravelled and denounced his life’s work on his deathbed. So there’s that.)
So… Do shampoo bars contain SLS?
There is evidence that SLS causes hair loss but no evidence to date that shampoo bars cause heavier hair loss than that initiated by liquid shampoos. SunKissed makes a shampoo bar and a conditioner bar without SLS, as does Green + Lovely and Whiff Botanicals.
So go on, save a fish and your hair might just love you for it. Shampoo walked into a bar and it’s here to stay.