Why Your Curls Are Dry and Frizzy: The Long-Term Impact of Sulphates and Silicones

It’s no secret that curly and wavy hair requires a little extra TLC. If you’ve been struggling with frizz, breakage, dryness, or curls that have lost their natural shape and bounce, the culprit might be hiding in your bathroom cabinet.

Many of us grew up using standard high-street shampoos and conditioners without a second thought. However, most of these products are formulated with harsh surfactants (cleansing agents) designed for “all hair types”- which often means they aren’t gentle enough for the unique needs of curly hair.

When we use these traditional products, we often enter a cycle of stripping the hair with harsh detergents and then masking the dryness with conditioners that coat the hair rather than treating the underlying issue. Over time, this can lead to curls that feel heavy, look dull, and lose their natural definition. It can also contribute to brittle, weak, and damaged curls.

The main culprit ingredients behind this cycle are sulphates and silicones.

Sulphates: Why They’re Too Harsh for Curly Hair?

You know that rich, bubbly lather you get from most shampoos? That’s usually the work of sulphates, such as Sodium Lauryl Sulphate.

While sulphates are effective at removing grease and product build-up, they can be too harsh for curly hair. They act like a strong detergent, stripping away essential moisture and the natural oils curly hair relies on to stay soft, flexible, and defined.

Curly hair is naturally drier than straight hair because the scalp’s natural oils have a harder time travelling down the twists and bends of the hair shaft. Curly hair is also brushed less frequently, meaning those oils aren’t distributed evenly through the hair. This makes curls more prone to dryness and frizz.

The long-term impact: Over time, repeated dryness prevents the hair cuticle from sitting flat. This leaves curls feeling rough or straw-like, looking dull, and becoming far more prone to frizz as moisture from the air enters the hair unevenly.

Silicones: Why Aren’t They Good for Curly Hair?

To compensate for the dryness caused by sulphates, many traditional conditioners and styling products rely on silicones. Silicones act as a synthetic coating — similar to a very thin layer of plastic — wrapping around the hair strand to create instant smoothness and shine.

At first, the hair feels silky and looks healthy. However, most silicones are not water-soluble, meaning they build up on the hair over time. This creates a waterproof barrier that’s difficult to remove without returning to harsh sulphate shampoos.

The “suffocation” effect: This silicone layer can prevent moisture from penetrating the hair shaft effectively. While curls may appear shiny on the outside, they can become dehydrated on the inside, leading to weighed-down curls, loss of curl pattern, brittleness, and split ends.

The Solution: What Do Curls Actually Need to Thrive?

The good news? In most cases, this damage isn’t permanent. Curls can bounce back beautifully once they’re given the right care.

To achieve healthy, defined curls, it’s essential to break the cycle of stripping and coating. Wavy, curly, and coily hair thrives when it’s hydrated from the inside out.

Gentle cleansing:
Start with a sulphate-free shampoo or cleanser. A gentle cleanser effectively cleanses the scalp and hair without removing the natural oils needed for curl definition and moisture balance.

Silicone-free conditioning:
Follow with a silicone-free conditioner to detangle curls while adding moisture and shine without build-up.

Deep hydration:
Once the silicone barrier is removed, your hair can finally absorb the moisture it’s been missing. A hydrating hair mask helps restore internal moisture and strengthen the hair shaft. This doesn’t need to be used every wash - once every couple of weeks is often enough.

Styling without build-up: For long-lasting hydration and defined curls, swap heavy, silicone-based stylers for lightweight, silicone-free curl creams and curl gels. These help smooth frizz, enhance curl pattern, and maintain softness while allowing your hair to breathe.