Dear Valerie: There is a lot of buzz on the internet about carbonic acid shampoos helping prevent hair loss. I haven’t really heard of this active ingredient, what’—CARBONIC CURIOUS

Dear Carbonic:
Any time there is a claim about an ingredient regrowing hair or preventing hair loss, I’m immediately skeptical. Maybe I’ve been spending too much time with my podcast co-host, Perry Romanowski, but I truly believe if something really worked to grow back hair or prevent it from falling out, a large drug company would invest the money to have this ingredient approved as a drug. Carbonic acid is not approved on any monographs by the FDA, so I have to remain skeptical about its efficacy in topical systems for hair.

How did carbonic acid get its renown for preventing hair loss? Well, I don’t know if I would say renown because there is no scientific literature that I could find reviewing the impact (positive or negative) about carbonic acid on hair or scalp. There is also no literature from ingredient suppliers, which is probably an even bigger red flag. And when you think about it, why would there be?

Carbonic acid is important in humans, but not for hair loss. It plays an important role in breathing. Carbon dioxide is a waste product in cellular metabolism. Carbon dioxide is converted to carbonic acid on our blood cells, and the reaction is reversed in our lungs by carbonic anhydrase so we can expel the CO2 into the air.

In cosmetic products, carbonic acid is essentially carbon dioxide dissolved in water and this reaction is readily reversible. Carbonic acid in water is incredibly unstable, and will convert back to carbon dioxide and disappear into the air. Carbonic acid is unlikely to be present during the shelf life of the product.

A few gimmicky-looking brands present carbonic acid technology in their products, claiming it will help with hair loss caused by sebum plugs. This elicits a bit of a chuckle when you think that hair loss is well-established to be an internal biological process (primarily involving DHT). In keeping an open mind, hair loss can occur for other reasons, but it’s unlikely sebum plugs is the primary reason, or that carbonic acid loosening sebum plugs is going to be the game changer.

Two brands of aerosolized carbonic acid shampoos purport to use 8,000 ppm of carbonic acid to combat sebum plugs that don’t get loosened with ordinary shampoo. They go on to state the reaction between the carbonic acid and sebum plugs won’t interfere with the ability of the shampoo to actually clean your scalp. Which one is doing the work—the carbonic acid or the actual shampoo? As an aside, even if the 8,000 ppm of carbonic acid formed from carbon dioxide was stable, it is likely overshadowed by the “LPG” (liquid petroleum gas) used to pressurize their product. People really need to use proper INCI names!

One of the two aforementioned brands claims their carbonic acid shampoo blocks DHT, which can minimize hair fall and aid in future hair growth. There is no scientific data to support this—not on their website, not in literature, not anywhere.

Another carbonic acid shampoo brand doesn’t mention sebum plugs but purports the benefits of carbonic acid for increasing circulation and micronutrients to the hair follicle. Again, there is also no scientific literature I’m aware of to support this claim. Unfortunately, their source of carbonic acid is PEG/PPG-75/25 Carbonic Acid Copolymer, which is a hair styling polymer. I guess it’s good enough to just have carbonic acid in the name.

Hopefully this gives you an understanding of what carbonic acid is (or isn’t) in shampoos.


Dear Valerie: I own a small lab consultancy where I create formulas for clients. I am having a hard time getting ingredient samples from suppliers directly to make formula submissions, conduct stability and run PET. I’ve been cut off! What’—BEAKER HALF EMPTY

Dear Beaker:
Getting ingredient samples for projects can be tough, even for established brands, so I can imagine the difficulty you’re experiencing with your small business. In order to make formulas, we chemists need ingredients. If you work at a contract manufacturer, you have all the ingredients you need at your fingertips. If you formulate at a brand, you stock your lab up with ingredients from manufacturing partners and supplement additionally with ingredients directly from ingredient suppliers. If you’re a consultant, resources in both these avenues are considerably more slender. Why can’t independent formulators just call up ingredient suppliers and be stocked aplenty?

If you were cut off from receiving samples, I’m going to bet the ingredient suppliers weren’t seeing a return on their [small] investment. Let’s look at it from their perspective. For every sample that’s requested and fulfilled, the ingredient supplier has to justify the cost of the expense to create the sample and mail it to you. The justification is usually that you have an active project that will use the ingredient, and it will eventually lead to a sale. If you are only sampling, using resources, and not generating sales, it becomes increasingly difficult for an ingredient salesperson to justify to their company owners why they should keep sending samples.

This is where industry relationships become very valuable; when I started my own lab, I had to stock up on ingredients in order to get to work. I pulled every relationship string I had from my decades-plus experience and explained some of my ingredient requests were for active projects, but others were simply to have in my lab just in case. The ingredient companies knew who I was because of our longtime relationships, existing track record, and were happy to help. If you don’t know who you are requesting ingredients from, get to know them so they know more about you and how you can partner together. If you are just getting started, considering joining your local society for cosmetic chemists to get to know people near you in the industry.

Transparency is also key. Being open and honest about what project the sample is for, whose brand will be using it and where it will be manufactured is helpful in justifying the sample expense. Of course, you may still need to show you’re an established business with a commercial mailing address. There are many liabilities for large companies to ship ingredients to residential addresses and individuals inexperienced with chemicals.

If you still have no luck or don’t have existing relationships, many independent formulators stock up their lab by buying ingredients from resellers. This is probably the least ideal because of the price and lack of technical support available—they don’t usually have experienced cosmetic chemists with industry expertise. One other challenge is lack of transparency in ingredient sourcing. You never really know who the original manufacturer is, and they can reserve the right to change their supplier at any point in time. If the manufacturer your client uses buys from these resellers anyway, it’s probably a viable solution and you can build in the cost of buying lab ingredients into your formula price. Just promise not to use Amazon!

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Valerie George
[email protected]
 
Valerie George is a cosmetic chemist, science communicator, educator, leader, and avid proponent of transparency in the beauty industry. She works on the latest research in hair color and hair care at her company, Simply Formulas, and is the co-host of The Beauty Brains podcast. You can find her on Instagram at @cosmetic_chemist or showcasing her favorite ingredients to small brands and home formulators at simply-ingredients.com