Sulfate Free Shampoo: What You Need to Know

Breaking down the ins and outs of sulfate free shampoo.

For a while there, it seemed like sulfate free shampoos were more like a fad than a mainstream hair care choice, just like cold wave lotion or organic products. Cut to today, and sulfate free shampoo is virtually a must-have for anyone with color-treated hair. Now found nearly everywhere from salons to your local drugstoremaking them as accessible as regular formulationseven products such as sulfate free shampoos for natural hair are no longer niche haircare items.

Before we deep-dive into this any further, first, the basics: What are sulfate free shampoos and how do they work? To answer some of these burning questions, including whether or not they are ideal for your particular hair type, we enlisted the help from Unilever’s R&D expert Leon-van Gorkom to help shed light on this popular dyed hair must-have. Read on to learn the truth:

textured waves tutorial with roughed up curls

1. What are sulfates?

According to Leon-van Gorkom, “Sulfates are anionic surfactants. They are frequently used in shampoos and body washes as they provide ample lather. [These are] SLS, short for sodium lauryl sulfate, and SLES, or sodium laureth sulfate, which contains ethoxy groups in the fatty acid chain and makes this surfactant milder than SLS. These surfactants are used with co-surfactants, normally betaine, to get an even milder surfactant system. Surfactants are cleansing agents that remove oil, dirt and styling residue from your hair.”

sulfate-free shampoo pink
Certain pigments, like pink, blue and ashy tones, fade quicker and may benefit from less washings.

2. Why go sulfate-free?

People with very sensitive skin might have negative reactions to sulfates. It can cause skin irritation and itching for some people. Those with dyed hair also use low-sulfate or sulfate free shampoo to help retain their color. Nexxus New York Salon Care Assure Rebalancing Shampoo and Nexxus New York Salon Care Color Assure Rebalancing Conditioner works well to clean and nourish your hair while also protecting your color from fading.

sulfate free shampoo on blue hair
Lower-sulfate shampoos and conditioners are also a great option to try.

3. What’s the buzz on low-sulfate products?

If you have sensitive skin but don’t know about specific allergies to sulfates, try a low-sulfate option. Products with a low amount of sulfate will still give you a good lather and clean without stripping your hair and scalp. Suave Professionals Keratin Infusion Smoothing Shampoo and Suave Professionals Keratin Infusion Smoothing Conditioner are low-sulfate options that help give you sleek, frizz-free hair.

sulfate-free shampoo on keratin treated hair
Those with Japanese-rebonded hair don’t necessarily need to use sulfate-free shampoo.

4. On keratin hair treatments and sulfates:

If you’re thinking about getting a keratin treatment, you might want to consider trying a sulfate-free shampoo. Since the keratin treatment washes out, the gentler you wash your hair, the longer the effects will last. Using an SLS-free shampoo can be less stripping and may help hold onto your keratin treatment for much longer. However, according to Leon-van Gorkom, “Other straightening treatments, like the Japanese rebonding treatment, don’t necessarily require the use of a sulfate free shampoo.”

He noted, “There are many definitions of keratin treatments: Some are purely cosmetic (deep conditioning), while others rely on chemicals.” He adds, “Some manufacturers of chemical straightening keratin treatments recommend their own sulfate free shampoos to avoid washing out the benefits prematurely. Also, just because the shampoo is sulfate-free does not mean it is milder. We also haven’t seen any data that color retention with sulfate-free shampoos is better than sulfate-containing shampoos, as color loss is predominantly driven by water, which is actually what swells the hair and allows hair dye particles to leach out.”