
The Curly Girl Method has long been lauded as THE gold standard of curly haircare. But are all of its rules scientifically accurate? I decided I wanted to find out.
How I got here
For those of you that follow me elsewhere on the internet, this post should not come as a surprise. After following the Curly Girl Method for a few years (more info here) I started to doubt its “miraculous” effects. Is avoiding “bad” ingredients what made a difference for my hair? What about my styling routine? The fact that I stopped using a flat iron? Started paying attention to my hair’s needs? I had told my thousands of followers that sulfates, silicones, and other ingredients were damaging to their hair…could I have been wrong?
Eventually, I came to terms with the fact that I am not a formulator/scientist. I have no idea why an ingredient would be included in a product or not. What products had I avoided because they had one “bad” ingredient? What other claims had I believed?
So I reached out to a cosmetic scientist, @dr.ginza, to help me sort through the nonsense. Dr. Ginzburg is a trained and licensed Pharmacist with a PhD in pharmaceutical analytical chemistry and over 15 years of research and development experience in the cosmetics and personal care industry. She’s worked with brands such as The Body Shop, Coty, and Beirsdorf, just to name a few.
So let’s hop right into it! Watch my video below or scroll for the text version.
CLAIM: The Curly Girl Method says sulfates should be avoided. ALl shampoos with sulfates are drying.
DR. GINZBURG: Sulfates cover a wide variety of ingredients. Upon searching a popular cosmetic database for “sulfate,” you will receive over 400 hits.
Some sulfate shampoos can be very “stripping,” i.e. they remove a lot of oily residues (sebum and dirt) from the hair which can be perceived as harsh. But sulfates aren’t the only surfactant which do this!
In addition, sulfate shampoos aren’t necessarily harsh or drying across the board. When formulated with replenishing and conditioning ingredients in a well thought out formulation, and when combined with other secondary surfactants, the shampoo may not be drying at all. It all depends on the formulation.

CLAIM: Silicones should be avoided. They build up on the hair, prevent moisture from getting in, and can only be removed with sulfates.
DR. GINZBURG: Silicones are an immensely large group of molecules. To say silicones should be avoided is a very generalized statement.
Some silicones are volatile and evaporate after a formulation has been applied. Other silicones are meant to be deposited on the hair to give it a smooth feel and can be very beneficial for damaged hair. Some are even used as emulsifiers and help stabilize an emulsion-based formulation.
All silicones have slightly different properties. (Sensing a theme here?)
CLAIM: Waxes, butters, and non-natural oils such as beeswax, shea butter, and mineral oil should be avoided. They build up on the hair and are difficult to remove.
DR. GINZBURG: How a lipid deposits on the hair very much depends on the entire formulation.
Singling out ingredients without taking respect to their concentration and how they are formulated does not make any sense.
CLAIM: Certain alcohols should be avoided because they’re drying. (Ex. isopropyl alcohol)
DR. GINZBURG: Again, this depends on how it is formulated. An alcohol by itself might be drying, but if it is formulated with thought and in the company of the right ingredients it can be used in moisturizing and nourishing formulations. Calling out individual ingredients without taking respect to their concentration and how they are formulated does not make any sense at all. Ingredients by themselves are not the same as a final formulation.
CLAIM: It’s safest to avoid parabens in favor of other preservatives. They are cancer-causing.
DR. GINZBURG: We have no data that show that the parabens that are approved for use in cosmetics do cause cancer. In fact, those parabens have been used for a very long time and repeatedly been shown to be safe for use in cosmetics and personal care products.
It is very important to understand that parabens (as well as the other groups of ingredients we are discussing here) are a group of ingredients. “Paraben” means that the molecule in question is structurally related to other PARAa-BENzoic acid esters. There are plenty of different structures that fall into this category. The ones that we use in cosmetics are demonstrably safe. To generalise that “parabens” as a group do something again does not make any sense, we need to be more differentiated when looking at ingredients.
Using other, newer preservatives is of course an option if one really doesn’t want to use parabens, however as we have less safety data for those simply for the fact that those are newer substances and there is not as much information about them available compared to what we know about paraben. In addition, there is a greater risk of allergic reactions or contact dermatitis to be induced by newer preservatives.
CLAIM: Plant-based, chemical-free formulas are the safest. Synthetic ingredients are more likely to be toxic.
DR. GINZBURG: Whether an ingredient is plant based or synthetic does not say anything about its performance, its safety or its impact on the environment. This is a common misconception.
All matter is made of chemicals, there are no chemical-free products. In fact, the Royal Society of Chemistry in the UK has put out a reward of 1 million GBP for anyone who can formulate a chemical-free product because this is sheer nonsense.
The safety of a product or an ingredient depends on its concentration the individual ingredients are used at and the purity or quality of the ingredients. It is very easy to formulate a completely natural product that is full of dangerous compounds, contaminated, and dangerous to use. Safety and the origin of an ingredient do not have anything to do with each other. Many companies use this notion to scare their potential customers into buying their products.
If none of the ingredients banned by the Curly Girl Method are “bad”, how can we find the best products for our hair? Can marketing be trusted?
DR. GINZBURG: I would recommend trusting a professional hairdresser: they are professionally trained for many years and know about hair and products. After that finding a product that works for you, that you enjoy and that makes your hair look the way you like is what is most important. If the Curly Girl Method works for you and you are happy with your hair there is nothing wrong with it. I would recommend to take marketing claims with a grain of salt at least in the US and certainly be critical. In the EU claims are more tightly regulated but even here companies and brands often make outrageous statements about ingredients.
What I would look out for and be cautious of undifferentiated blanket statements that demonize entire groups of ingredients without further explaining them. In addition, companies that use fear or shame as a sales tactic should not be trusted from my point of view. If you need to be scared into buying their products, how good can they actually be? Often the really great performing products that become consumer staples and gain iconic status are the ones that are formulated with superior or new technology and they are products that work for many people.
I wonder if we were to inform consumers about the great technologies in our products and how they perform instead of scaring them and telling them about all the things that our products are NOT doing, how many brands had absolutely nothing more to say than “clenases” and “conditions” in the hair product arena. Formulation is complex and so is the world of ingredients.
Final Thoughts
To be clear – as Dr. Ginzburg mentioned, I am not telling you to stop following the Curly Girl Method f it works for you. I am asking that you stop demonizing ingredients as “toxic” or “bad,” understand that all of the ingredients discussed here can have a place in a healthy hair routine, as well as acknowledge that we are all laymen without the ability to properly evaluate a formula or the body of scientific research (& while we’re on the topic – EWG and ThinkDirty do not count as trustworthy sources ?).
Want more information on this topic? Don’t reach out to me – leave it to the professionals! Here are a few accounts I recommend following on Instagram for more information: