Co-Wash vs Shampoo: What’s Best For Curls?

There are four types of surfactants: Anionic, cationic, amphoteric and nonionic. Anionic surfactants such as Sodium Laureth Sulfate are the strongest and have a high pH that lifts away build-up but also strips the hair clean of its natural sebum, leaving the cuticle raised and lifted. This can lead to dry hair, friction, protein loss, and frizz, especially in curly hair that is naturally drier. 

However when anionic surfactants are combined with other nonionic surfactants they become milder. Sulfate-free shampoos often contain mild anionic surfactants such as Sodium Methyl Cocoyl Taurate and nonionic surfactants such as Lauryl Glucoside. Sulfate-free shampoos are a great option for naturally curly hair because they often lather well, can remove build-up, and won’t strip the hair. 

Co-washes often contain cationic and/or amphoteric surfactants, which are mild detergents in comparison to anionic surfactants. Behentrimonium Chloride is a common cationic surfactant found in co-washes. It functions as a hair conditioning agent and has a low pH, similar to the hair’s natural pH which keeps the cuticle smooth. Cationic surfactants are positively charged, therefore they bind to the hair. Co-washes that only contain cationic surfactants will not effectively remove dirt and oils. However, when combined with amphoteric surfactants, a co-wash is able to lift away some of those impurities. Amphoteric surfactants are still mild with a low pH, but the pH is slightly higher than the hair. A common amphoteric surfactant is Cocamidopropyl Betaine, derived from coconuts. 

The Curlsmith Curl Quenching Conditioning Wash is a co-wash that contains both Cocamidopropyl Betaine and Behentrimonium Chloride, making it the perfect balance of gentle yet effective. 

Low-poo is a term that defines low-lather shampoo. These types of shampoos often contain non-ionic surfactants that are foaming agents, such as Lauryl Glucoside. Low-lathering shampoos are a great alternative to co-washes for those with fine hair because they have a liquid formula like traditional shampoo. This makes them more lightweight compared to the cream-based formula of co-washes. Low-poo shampoos are very gentle and non-stripping yet provide a small amount of foam. 

Essential Moisture Shampoo is a very gentle low-poo cleanser that offers the look and feel of a traditional shampoo. It’s non stripping, moisturizing formula makes it suitable for frequent washing, helping to cleanse the hair and scalp without compromising moisture. It’s suitable for curl types, textures, and porosities. 

If you are sensitive to fragrance or you have a sensitive scalp, try the Fragrance-free Shampoo instead. This fragrance-free cleanser is dermatologically tested to give a gentle cleansing without stripping the hair. 

Classic sulfate-free shampoos typically offer a medium to strong lather and cleansing ability, depending on the formula. The surfactants range from Sodium Methyl Cocoyl Taurate, Cocamidopropyl Betaine, and Decyl Glucoside. All curl types can benefit from a classic sulfate-free shampoo and should incorporate them at least once per week to avoid build-up. 

Curlsmith’s Frizz Control Shampoo falls into this category. It is suitable for frequent washes because it’s mild, but it provides a little bit more foam in comparison to low-poo options. The shampoo helps prevent unwanted frizz, leaves the hair soft and manageable, and is suited to all curl types, textures, and porosities. 

If you require a shampoo with added protein ingredients, try the Core Strength Shampoo which is particularly beneficial for damaged and high porosity hair, however, all hair types can use it to help achieve the right protein moisture balance in the wash routine.

Shampoos with sulfates remove all product and sebum build-up but can often leave the hair and scalp feeling stripped. Fortunately, there are sulfate-free clarifying shampoo options. These often use a combination of anionic surfactants and amphoteric surfactants. Clarifying shampoos often have the most foaming ability to reach the scalp and cleanse deeply. 

Curlsmith Curl Reset Detox Shampoo is a sulfate-free clarifying shampoo formulated with micro-fine scrub particles to gently exfoliate the scalp and remove build-up. It contains a chelating agent that help effectively remove 8 hard water minerals, along with Apple Cider Vinegar, known for its clarifying properties, and Peppermint to help leave the scalp feeling refreshed. Suitable for all hair types, textures, and porosities. 

With so many different types of hair cleansers available, how do you know which one is right and how often to use them?  To reap the benefits of both a co-wash and a shampoo, you can incorporate them both in your routine by alternating each wash day. Co-washes or low-poos could be used mid-week when perhaps you want to quickly restyle and your scalp is not very dirty with build-up.  

Co-wash is best for all curl types, porosities, and medium to coarse textures. It’s particularly beneficial if you need to wash frequently due to exercise or active lifestyle.  

Sulfate-free shampoo is suitable for all curl types, textures, and porosities. They can be used 1-2 times per week to remove all oils and product residue. For a deeper cleanse, a clarifying shampoo is ideal to use every 4-5 washes.  

While using both co-wash and shampoo can offer benefits of both hydration and effective cleansing, not everyone needs both in their routine. The right approach depends on your hair type, lifestyle, scalp condition, and how often you wash your hair. If you cleanse infrequently (once a week or less) or are prone to build up, shampoo alone will be sufficient. However, if you choose to incorporate a co-wash, it should alternate with a shampoo rather than a complete replacement as regular shampoo is still needed to thoroughly cleanse the scalp and remove accumulate build up. For guidance on building the best regime for your curls, explore our curly hair routine guide.