What Does Sulfate Do To Your Hair?

You have probably seen or heard the phrase “sulfate-free shampoo” tossed around when browsing beauty and hair products online. But what exactly does it mean, and what is sulfate in the first place? We will answer these questions, and a few others to educate you on the science behind sulfate, why it has been a hot ingredient in hair care products in the past, and why many industry leaders are now shifting away from sulfate.

What is Sulfate? 

Sulfate is a salt compound that forms when sulphuric acid reacts with other chemicals. There are many different kinds of sulfates, which are used in everything from toothpaste to detergent to— the reason we’re all here—shampoo.

Sulfates, in general, are used as cleaning agents. ‌

In hair care products, one of two sulfates is typically used: Sodium Lauryl Sulfate or Sodium Laureth Sulfate. Sodium Lauryl Sulfate, or SLS, is actually the parent compound to Sodium Laureth Sulfate, or SLES. While there are some key differences between Sodium Laureth Sulfate vs Sodium Lauryl Sulfate, both are common shampoo ingredients for a couple of similar reasons (more on these below).

Why Sulfate is Used in Hair Care Products

The two major reasons SLS or SLES are used in shampoo, conditioner, and hair styling products are:

‌1. For A Powerful Clean

We all use shampoo for the same reason: to cleanse our hair. Sulfate is a popular ingredient in shampoos because of its incredible ability to cleanse. The compound bonds with both water, allowing it to penetrate wet hair, and oil, allowing it to pull oil, dirt, and grime from the hair. The result is a powerful clean.

2. For a Rich Lather

Sulfates are great foaming agents that produce a rich lather when combined with water. That sudsy texture and full feeling you get from shampoo are because of a surfactant in the formula, such as sulfate.

What Does Sulfate Do to Hair?

In addition to cleansing hair well by removing oil and impurities, sulfate affects hair in other less-great ways.

Causes Dryness

 As we mentioned above, sulfate bonds with oil and removes it from the hair really well— sometimes too well. Sulfate shampoo can strip the hair of too many of its natural oils, leaving it dry, rough, and brittle. This may not be an issue for those with oily hair. But anyone with dry hair already or fine hair that is prone to damage will lose what moisture they do have, leaving their hair lacking in shine and vibrancy and vulnerable to breakage.

Irritates the Scalp

Sulfates can be harsh on the skin, which includes the scalp. SLS, in particular, can be extremely irritating, especially for anyone with sensitive skin or preexisting skin conditions. If a sulfate-containing hair product is causing scalp irritation, signs include a flaky or itchy scalp and/or red patches.

Fades Color

Sulfate is not only harsh on the skin but also on hair color. Sulfate shampoo can quickly cause colored hair to fade or become dull.

Why Sulfate Free Products are Becoming Popular

Anyone who experiences dryness, damage, irritation, and/or colors their hair should steer clear of sulfate-containing hair products, which is a large portion of shampooing customers. For good reason, then, the industry has shifted to produce less harsh, more hydrating, color-safe formulas that appeal to these customers, like our color safe shampoo and conditioner. Insert sulfate-free shampoo.

Safe-For-Everyone Sulfate-Free Shampoos

We’re not shy about our shampoo ingredients here. In fact, they’re our pride and joy. At Living Proof, we know the science, so we can create the ingredients that are the best possible for your hair (we’re talking results). We steer clear of harsh chemicals, including certain sulfates, and opt for tried and true ingredients that not only do the job but do it better and safer. ‌

This is why all of our shampoos are sulfate-free (SLS and SLES). But what is “What is sulfate free shampoo?” We don’t use sulfates (SLS or SLES) in our shampoo formula. For science-backed hair care for every hair type and concern, from hair repair products for damaged hair to curl-enhancing treatments, find the right sulfate-free hair care routine for you with Living Proof.

While we’ve created unique shampoos for every hair type in the book, our Perfect Hair Day™ shampoo is suitable for most hair types. It’s sulfate-free, silicone-free, and safe for color and chemically treated hair, so it’s a great place to start if you’re in the market for a sulfate-free formula.

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Living Proof Review Team

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