OK, What Are Sulfates? And Are They *Really* Bad for Your Hair?

Nowadays, you can’t reach for a shampoo without seeing the words ‘sulfate-free’ displayed in bold on the bottle. The second I made my switch to curly hair products, any utterance of the word ‘sulfates’ was followed by a gasp in the natural hair community. But while brands slap ‘sulfate-free’ on their products for marketing purposes, do we really know why they’re so bad? We tapped Dr. Eylse Love, a dermatologist at Glamderm and Spring Street Dermatology, to explain what sulfates are and if we should really be avoiding the ingredient at all.

“The term ‘sulfates’ is colloquially used to refer to a type of cleansing agent—sulfate-containing surfactants. Surfactants are chemicals that effectively remove dirt from surfaces,” said Dr. Love.

From your scalp to your floors, they work to remove dirt, oil and any product buildup. (Basically, they keep things squeaky clean and brand new.) The key ingredient is often found in beauty and home products like shampoos, body wash, detergents and toothpaste, to name a few.

There are many types of sulfates, but the most popular ones (that are found in most products) are sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES). What’s the difference though? It all comes down to the cleanse factor. “In terms of cleansing ability, SLS is king. However, SLES is a close relative,” she explained.

Sulfates used to be a staple in beauty products dating back to the 1930s. But news began to make waves in the ‘90s that the ingredient caused cancer (which was proven false). Since then, many have questioned the importance of the ingredient and if we actually need them in our beauty products at all—and while they might not cause cancer, the answer is still a resounding “no,” they’re not necessary. Here are a few reasons why you might want to avoid sulfates:

1. They can cause side effects over time. The components found in sulfates can be irritating to your skin, eyes and overall health, especially for people with sensitive or dry skin. They can cause side effects like dryness, acne and redness based on the amount of sulfate you consume over time.
2. They’re not great for the environment. The use of sulfates actually affects climate change. The chemical gases in the product you wash down the drain can eventually make their way to sea creatures.

Here’s the slightly confusing part—sulfates can have their place. They work hard to help keep your hair clean, which is why they’re often included in shampoos in the first place. “Sulfates containing surfactants help to cleanse the hair by binding to dirt and product buildup and allowing that dirt to be rinsed away by water,” Dr. Love explained. “This results in a clean hair shaft that can better bind to products, including conditioners and styling gels.”

The thing is, not everyone needs that. And they’re a little bit too good at removing things—including your natural oils. As a result, they can leave hair looking and feeling dry, dull, frizzy and brittle. Plus, they might irritate your scalp since they draw out so much moisture. The more you use products with sulfates, the more your strands will be prone to breakage and split ends.

People prone to dry hair (aka those with curly, coily or color-treated hair) should especially steer clear of sulfates. But one hair type, in particular, might benefit from the ingredient from time to time: “[Sulfates] can be very helpful for those with oily hair that falls limp from excess oil production,” explains Dr. Love.

FYI, just because a product says its sulfate-free doesn’t mean it’s completely free of toxic materials. A beauty item might not have SLS or SLES, but it could still include hidden ingredients that stem from the same family. While SLS and SLES are the most common, here are a few others you should know and look for:

• Sodium Lauroyl Isoethionate
• Sodium Lauroyl Taurate
• Sodium Cocoyl Isoethionate
• Sodium Lauroyl Methyl Isoethionate
• Sodium Lauroyl Sarcosinate
• Disodium Laureth Sulfosuccinate

Aside from checking the label, an easy alternative is to look for solid or oil-based products to swap out your sulfate items. Or, consult with a medical professional for any sulfate-free recommendations.

Yes….and no. At the end of the day, it depends on the amount you use and your hair type. “There's a misconception that sulfate-containing surfactants are 100 percent bad. The truth is, they are excellent cleansers,” she expressed. “For those with fine, oily hair, they can be helpful on a routine basis to control oil buildup and allow styles to hold for longer.” 

If you do decide to reach for a sulfate cleanser or shampoo, Dr. Love recommends a good moisturizer or conditioner to keep your hair and scalp hydrated. Like Dr. Love mentioned, small amounts of sulfates are actually completely safe (and backed by the FDA). And there are gentler surfactants out there (aka ammonium laureth sulfate and sodium slykyl sulfate) that you can try if you need a deep clean. However, irritation and other side effects (aka acne and clogged pores) can still occur, especially for people with sensitive or dry skin.

The best thing you can do is look over the ingredients list on your products and research science jargon that you’re not familiar with. You should be aware of what you’re putting on your hair. There are plenty of products out there that can keep your hair clean and healthy without causing irritation, hurting the planet or turning into a frizzy mess (because let’s face it—no likes frizz.)

Shop the sulfate-free products: Carol’s Daughters Black Vanilla Moisture & Shine Sulfate-free Shampoo ($11); TGIN Sulfate-Free Shampoo ($13); Girl + Hair Cleanse+ Water-to-Foam Moisturizing Sulfate-Free Shampoo ($13); Matrix Biolage 3 Butter Control System Shampoo ($20); Living Proof Perfect Hair Day Shampoo ($28); Hairstory New Wash Original Hair Cleanser ($50); Oribe Moisture & Control Deep Treatment Masque ($63)