Sulphates 101: What are they and how do they affect wavy hair?

Sulphates, like blue Smarties, are one of those ingredients people warn you about without really explaining why.

They’re often labelled as bad, harsh, or something to avoid at all costs.

The truth is a little more complicated, especially for wavy hair.

Sulphates are cleansing agents used in shampoos that remove oil, dirt, and buildup from the hair and scalp.

They’re very effective at what they do. That’s why they’re commonly found in shampoos, especially ones that foam a lot and leave hair feeling squeaky clean.

Some of the most common sulphates you’ll see are sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES).

Wavy hair relies on moisture to keep its shape and softness. The bends and curves in each strand make it harder for natural oils to travel down the hair shaft, which means the lengths often struggle to stay hydrated.

Sulphates don’t just remove dirt, they remove oil. And when they’re used too often or are too strong for your hair type, they can strip away the oils your waves are actually crying out for.

You might notice:

• Your hair feels dry or fluffy straight after washing
• Increased frizz, even when styling carefully
• Waves that lose definition or feel harder to manage

In a panic, the scalp may produce more oil to compensate, leaving you stuck with greasy roots and dry ends.

Straight hair tends to distribute oil more easily, so it can sometimes tolerate stronger cleansers. Wavy hair, on the other hand, already struggles with moisture balance.

When that balance is disrupted, waves can become unpredictable, flat in some places, frizzy in others.

It’s not that sulphates “ruin” your hair. But they can hurt hair that already needs a little extra support.

Not necessarily.

There are times when a stronger cleanse is useful, for example, when there’s heavy buildup on the scalp. The issue usually isn’t sulphates themselves, but frequency and context.

Using a strong sulphate shampoo every wash can be too much for wavy hair. Using now and then is a different story.

If your hair often feels dry, frizzy, or unsettled after washing, a gentler cleansing is usually a good place to start.

Look for shampoos that focus on cleaning the scalp without leaving hair feeling tight or rough.

Our Wavy Hair Cleanse Shampoo is a sulphate-free shampoo for waves. It lifts away build-up and refreshes your scalp without stripping the natural oils your waves need to stay soft and defined.

Are sulphates bad for wavy hair?

They’re not always bad, but frequent use can strip moisture that wavy hair needs to stay soft and defined.

Do sulphates cause frizz?

They can. By removing natural oils, they can leave hair drier, which often leads to increased frizz.

Should wavy hair avoid sulphates?

Not completely, but many wavies do better using them less often and choosing gentler cleansers for regular washes.