If you’ve seen the slew of new toothpastes hitting the shelves that are “SLS Free” or even “sulfate free,” you’ve probably been wondering “what is SLS, and what do I *actually* need to know about it? What’s the big deal?”
Let me catch you up: What is it? SLS is short for sodium lauryl sulfate and is a cleaning agent usually derived from coconut or palm oil. And although it is derived from natural sources, it’s actually a synthetic chemical.
Why is it used? SLS reduces surface tension, creates foam, cleans surfaces, and removes grease and oil stains. Also important to note, if you’re checking a product label for SLS it could be listed as sodium lauryl sulfate, or one of the ways it can be listed on the label. When in doubt, give it a google 🙂
Where is it found? SLS is found in many household cleaners such as dish soap, hand soap and laundry detergent. It is prevalent in all kinds of personal products, ranging from lotions to sunscreen and even hair dye. It is seriously everywhere. Unless you’ve consciously been shopping for SLS free or sulfate free products, chances are you’re using a fair amount of products with SLS.
Luckily, you don’t need to worry about most of the SLS in your typical daily use. The main concern with using SLS is that in topical applications, it could cause skin irritation. The potential irritation is caused when SLS stripps the skin of it’s natural oils and leaves behind dry and irritated skin. Of course, this bothers some people more than others — if you have sensitive skin it’s probably something you should start paying attention to, especially in your everyday skincare routine.
Why does SLS in toothpaste make a difference?
Similarly to the way SLS strips the skin of oils, “SLS actually strips away the protective lining of the mouth.” ( Says Dr. Mark Burhenne co-founder of Ask the Dentist.) And, as you might expect, stripping your mouth of it’s protective lining isn’t a good thing. A number of studies found, at least in preliminary results, that toothpastes containing SLS lead to an “increased incidence” of canker sores, aka my personal nemesis.
Canker Sores
Canker sores were understandable, expected even, back when I had braces, but that was over a decade ago! Up until pretty recently I was still getting them, and frequently too, usually at least once a week.
Why was I still getting these things? At this point, I had no idea what SLS free toothpaste was.
I first checked out an article on MayoClinic’s website on canker sores. And I was surprised to see that the second suggestion for what could be causing recurring canker sores (scientifically referred to as “recurrent aphthous stomatitis” or RAS for short) was using toothpaste or mouthwash with the ingredient sodium lauryl sulfate. I thought what are the odds that this one ingredient is in my toothpaste? Well, actually — those odds were pretty bad — an estimated 75% of toothpaste contains SLS.
I checked the label of my toothpaste, and sure enough, it was there. Ever feel like the whole world is out to get you, including your toothpaste? Yeah, me either, until that point.
I did a deep dive into SLS. I read all about it.
I learned that SLS also interferes with the way foods taste. You know that nasty bitter taste when you eat a grape (or something sweet) right after brushing your teeth? You can thank SLS for that. Weird, right? But this is because SLS temporarily blocks your taste buds from perceiving sweetness, and breaks down the phospholipids on your tongue which normally balance bitter tastes. Sweet foods won’t taste sweet, and bitter foods will taste even more bitter. Great, just what I’ve always wanted — NOT!
So somewhere between the canker sores and enhanced bitter taste, I decided to give this SLS free stuff a try.

Trying SLS Free Toothpaste
The first time I used my new SLS Free toothpaste I wasn’t really expecting it to be that different from normal toothpaste. I honestly thought I wouldn’t be able to tell a difference. Most of the time the “fake stuff” is almost the same as the real deal.
Not so for SLS free…
SLS free toothpaste is noticeably different. For starters, there isn’t a nice foamy experience we’ve all come to expect (or, dare I say, know and love) from brushing our teeth. Instead, you know how it feels if you brush your teeth shortly after eating cereal? Your toothpaste doesn’t really foam up and it feels… flat? Well, that’s a bit what SLS free toothpaste is like on the reg.
Yes, I do miss the bubbles. I’m not salty about it. Ok, maybe I am a little.
Bubble dilemma aside, there is an increasing variety of SLS free toothpastes available. But, lemme tell ya, they are *not* created equal. Some do a better job of replicating the foaminess of regular toothpaste.
Personally, my favorite is Hello Toothpaste which is available in my local grocery store, and is also available on Amazon. While it isn’t “foamy” it also doesn’t feel cereal-flat and I still get to enjoy a fresh and clean feeling after brushing. Most importantly, it keeps me canker free.
So, should you be using SLS free toothpaste?
If you hate that nasty taste of your OJ post toothpaste, or if you have recurring canker sores, you should definitely give SLS free toothpaste a try. It’s a simple adjustment, and could really help you! Just remember that when you go shopping, really pay attention to the label. Even toothpastes in the “natural” section of your store may still have SLS. Just because it is an organic brand of toothpaste, doesn’t mean it is SLS free. Happy SLS free brushing.