Since you’re here, you’ve likely heard that glycerin in toothpaste is a terrible, horrible, no good, very bad thing.
Many natural sources say that even though you’re already likely avoiding fluoride and that awful SLS (Sodium Lauryl Sulfate–a foaming agent) in toothpaste, you’d better be avoiding glycerin too.
As if we don’t have enough to be concerned about; now we need to worry about this, too?!
This sure is a hard pill (or blob of toothpaste) to swallow because glycerin is in most toothpastes–both conventional and natural. (Oh and if you’re using toothpaste with fluoride in it, do not swallow any toothpaste and DO call Poison Control if you do–but I digress).
Welp, never fear. I’m going to break this down for you and present you with a pretty solid debunking of this whole glycerin toothpaste myth.
Figuring Out What’s Healthy Is Hard
After awhile, all of this healthy living information gets really hard to wade through, doesn’t it?
First, you hear that eggs are bad for you, then they’re good.
It’s enough to make you want to throw in the towel and eat a pint of ice cream and several Snickers Bars.
Well, hold on.
Second, you’ll soon see that you probably don’t need to toss your toothpaste.
What Is Glycerin?
Also known as glycerol, glycerin is a natural compound derived from vegetable oils, animal fats, or petroleum through fermentation of yeasts, sugars, or starches. It’s clear, colorless, and odorless, and is very very sweet.
A Swedish chemist, Karl Wilhelm Scheele, accidentally discovered glycerin in 1779 when heating a mixture of lead oxide and olive oil.
It can be used as a candida-safe sweetener, like in these Homemade Sugar-free Marshmallows, but is also used in personal care products, like this Homemade Foaming Soap. It is also used in glycerites (which are another type of sweetener) and as the base for alcohol-free “extracts” like this Alcohol-free Vanilla.
What Is Glycerin Made From?
The most common sources of glycerin are natural–coconut, soy, and palm.
In the 18th and 19th centuries, people often used candles and soaps containing animal fat to make glycerin.
These days, plant based oils are more commonly used for making glycerine.
Petroleum can also be used to make glycerin but that method of making glycerin wasn’t discovered until 1948. It’s more costly to make glycerin this way so it’s not the source of most glycerin on the market.
If you’re concerned about GMOs, simply choose organic or non-GMO glycerin to avoid such concerns.
When I Almost Tossed My Toothpaste aka Negative Claims About Glycerin
I believe it was in the book Cure Tooth Decay where I first read that glycerin is bad for your teeth. The author stated that glycerin coats tooth enamel and that it can take a lot of brushing to get that coating off.
Oh the panic I felt when I ran to the bathroom, pulled out our natural toothpaste, and read the word “GLYCERIN” right there, in black and white on the label.
Here I was trying to be oh so healthy by choosing a natural toothpaste, and now this?!
As time went on, I heard more and more people talking about this.
I found some toothpastes without glycerin, but then later really needed remineralizing toothpastes, and guess what–they pretty much ALL had glycerin in them, so I hesitatingly bought some and used then, thinking “Well, it can’t be all that bad. Can it?”
Then recently, I started wondering again and started researching….and found some troubling information in the form of a sort of scary (to me) study.
That led to more research–which led to this post.
Did I Find the Study Proving Glycerin Is Bad for Your Teeth?
Most authors who claim that glycerin doesn’t prevent remineralization state that they can’t find a single study showing that glycerin is a problem.
That seemed to be the case, but one day, while reading through the comments of a post, I found it. Someone shared this study, saying that it showed that glycerin reduces the hardness of teeth.”
And yes, it seemed to do just that.
The Study Details
In the study, a variety of substances (including plain glycerin) were applied to prepared (dead) tooth fragments, and left there for 8 hours. Then the fragments were submerged in artificial saliva for 16 hours.
Here is what the researchers concluded:
Glycerin also presented slight decreases in microhard-https://www.researchgate.net/publication/7500507_The_effect_of_10_carbamide_peroxide_carbopol_andor_glycerin_on_enamel_and_dentin_microhardness
ness for sound enamel and dentin, similar to the effect
of carbamide peroxide. It could act as an adsorbed layer
barrier to artificial saliva and to a remineralizing effect.
At first glance, this seems to be the death knell for glycerin-containing toothpaste.
Not. So. Fast.
Problems With the Study
First of all, the control was a 10% carbamide peroxide solution. In their words “it [carbamide peroxide] is accepted as safe and effective by the American Dental Association (ADA)”
What that means is that the control substance had already been determined to not damage teeth, and glycerin performed better than the control in most aspects of the study.
The Artificial Saliva Factor
Note that all of the substances they tested showed decreased microhardness, but we don’t much about their artificial saliva except other studies they referenced where they used it. How do we know their saliva wasn’t already decreasing the micro hardness of the teeth?
It would have been much better to have water or another substance (xylitol, erythritol, or sorbitol would have been good options) as another control. Or their artificial saliva alone would have been good to have as a control to know what that did to the teeth.
Also note that the solution was “supersaturated” with minerals. That means that the water had so many ions in it that nothing else could dissolve in it. Think about what happens if you dump a lot of salt into a small glass of water. At some point, you just can’t dissolve any more salt into the water.
So, the artificial saliva was so saturated that the glycerin wasn’t able to dissolve and the minerals in the artificial saliva solution reach the tooth for remineralization. Nothing else could dissolve in the saliva solution–that really complicates things.
That’s Not How Toothpaste Works
While this study is interesting, it’s not how toothpaste works in the mouth.
Teeth don’t sit in a solution of toothpaste and saliva. Your mouth continually produces saliva (ever notice how your mouth fills up when you’re brushing?) Also, you rinse your mouth after you’re done brushing, and again, the saliva in your mouth isn’t supersaturated.
Who Started This Glycerin Myth?
It seems the whole demonizing of glycerin myth started with Dr. Gerald Judd (Chemistry Ph.D.) who wrote a lot about dental health a number of years ago.
Judd seemed to be trying to figure out ways to keep teeth healthy and had some interesting views.
originally claimed that glycerin leaves a coating on the teeth that according to him “takes 27 washes to get it off”.
He also said that
“teeth brushed with any toothpaste are coated with a film and cannot properly remineralize”.
Interestingly, he recommended brushing teeth with soap, (note that he stated that it only takes 2 rinses to remove soap from your teeth)–perhaps this is the first red flag since doesn’t that mean that his recommended soap is sticking to teeth too?
Others claim that not only does glycerin inhibit tooth remineralization, but that it’s a plaque magnet leading to the growth of bad bacteria, which can cause bad breath, gum disease, and even tooth decay. Yikes!
So I went on a hunt for another toothpaste and went on my way using another brand for awhile.
But the whole topic still bugged me from time to time, and at some point I decided to research it further.
Here’s what I found…..
Other Dental Claims By the Same Doctor That Don’t Make Sense
Dr. Judd didn’t write mostly about glycerin.
n fact, he didn’t write much about glycerin at all.
Most of what he wrote was about other tooth-related issues.
For some reason, however, this glycerin thing has gotten the most traction in the natural health arena,
Some of his other thoughts, well–
Just because someone makes incorrect (or even wacky) statements about other things doesn’t make their other claims wrong, but it can be a cause for concern. Either the person doesn’t know what he/she is talking about, doesn’t research well, is a sensationalist, is crazy, or is lying.
Dr. Judd, while he does have a much stronger background in chemistry than I do with my college level chemistry course, said some things about teeth that don’t make sense. You can find a short outline of some of his claims here, a letter to his followers here, and a full copy of his book, Good Teeth from Birth to Death here.
While Dr. Judd seemed to mean well, following are a few problems in his reasoning.
Brushing With Soap?
Dr. Judd claimed that instead of toothpaste, brushing with soap is the way to go, stating that you only need 2 rinses to get soap off of your teeth.
Doesn’t that mean that soap sticks to your teeth too? And if so, how many rinses is OK for something that you’re going to use on your teeth? 2 is OK but 27 isn’t? Is 5 OK?
Perhaps brushing with soap works, but there’s actually glycerin in most bars of soap, so this is all very confusing indeed.
Sugar Doesn’t Cause Cavities?
Dr. Judd also claimed that sugar doesn’t cause cavities.
Judd based this claim on what he saw after after adding sugar to bone material The bone material wasn’t affected negatively by the sugar.
Of course that’s not how cavities work. Sugar feeds the bacteria on the teeth which then deposit plaque on the teeth and then–you get cavities!
Bacteria Doesn’t Cause Cavities?
Judd said that since skeleton teeth buried in the ground didn’t have cavities, despite being in contact with bacteria in the dirt, that bacteria doesn’t cause cavities.
Of course there is no saliva in the dirt and the same carbohydrates and same strains of bacteria that are in the mouth are missing too.
This isn’t to say that Dr. Judd was stupid and that everything he said was wrong. However, it seems that his overall views on dental health were overly simplistic and didn’t take into account numerous important factors.
Evidence That Glycerin Is Actually GOOD for Your Teeth
So now that the sort of scary study about glycerin is debunked, and Judd’s reasoning is debunked, let’s talk about glycerin’s positives.
Of course we’re talking about other issues here more than what the FDA thinks about glycerin, but for the record, the US Food and Drug Administration recognizes glycerin as being safe.
There are also many studies showing that glycerin has beneficial properties.
While they aren’t all directly applicable to dental health, you can easily see the connections.
Reduced Streptococcus Mutans (source)
Reduces Biofilm (source)
Promotes Healing (source)
Is Sorbitol Better for Toothpaste Than Glycerin?
Some natural toothpastes use sorbitol instead of glycerin since sorbitol also acts as a sweetener and helps keep toothpaste from drying out (but it doesn’t have glycerin’s preservative properties.
It’s important to note that even though sorbitol isn’t nearly as cariogenic (causes cavities) like glucose, it still can lead to cavities. So though it doesn’t seem like a really big deal, technically it’s not the best thing to have in toothpaste (source).
Benefits of Glycerin in Toothpaste
Instead of being a bad guy, here’s why you should be glad glycerin is in your toothpaste.
Makes It Taste Better
Glycerin is sweet. So your toothpaste tastes better with it in there and you and your kiddos are therefore more likely to brush with it.
Prevents Toothpaste From Hardening (Becoming Cement)
Well, not really cement, but if you’ve ever left the cap off of your toothpaste, you know what I mean.
Glycerin is a humectant (it draws water to itself) so it helps keep toothpaste from drying out in the tube. Glycerin also has this function in my Moisturizing Homemade Foaming Hand Soap and it can be found in many skincare products and cleaners as well, to keep them (and you) from drying out.
As for toothpaste, glycerin prevents your toothpaste – and your mouth, for that matter – from drying out.
Interestingly, many artificial saliva products contain glycerin.
It’s Bacteriostatic (Kills Bad Bugs)
In light of the concerns about glycerin being unsafe for your teeth, this is really interesting to note. Not only does glycerin not stick to your teeth to prevent remineralization, but it so happens that it’s bacteriostatic and antimicrobial.
That means it actually does a lot more than just keep your toothpaste from drying out–it’s actually good for your teeth and can prevent cavities, periodontal issues, and even can help your teeth be whiter. (source)
Reduces the Need for a Preservative
When a formulation is 50% or more of glycerin, you shouldn’t need a preservative, which is great. I like avoiding the use of preservatives in my personal care products whenever I can.
Water and aloe in personal care products, on the other hand, are bacteria and mold breeding grounds, so glycerin is a much better base for toothpaste.
Natural Remineralizing Tooth Products I Love
While there are lots of natural toothpastes and dental health products out there that have some great reviews, I have a few favorites.
Theodent has theobromine in it, which seems to have valid research behind it showing that it is just as good as, if not better than, fluoride at keeping teeth healthy.
Great tasting flavors too, including Chocolate Chip for the kiddos :).
I bought several of these toothpastes when I was finishing up this post and I LOVE them. So zingy and my mouth feels AMAZINGLY clean.
I love the alkalinizing philosophy described on their site–makes a lot of sense!
Code WHOLENEWMOM gets a nice discount too!
I also LOVE this mouthwash from this company. It took away sensitivity on a tooth after just one use, and at my last hygiene appointment, my (very picky) hygienist said that my teeth had very little plaque on them and asked if I’d changed anything.
The only thing I’d changed was that I started using the mouthwash from here. Their other products look pretty great too, but I. Love. This. Mouthwash.
Yes, it’s not cheap but really you only need a teensy amount to get results. I try to stretch out my products whenever I can and you definitely can with this one. Just keep it in your mouth as long as you can.
Disclaimer: we’d just moved my hygiene appointments from 6 months to 4, so that might be part of it. However, when I started coming to their office I was on a 3 month schedule. So I think it’s more likely that this product is doing amazing things. Time will tell…..
Note that all of these products have glycerin. If glycerine was a seriously scary tooth enemy, there’s no way my dental health would have improved this quickly. Plus the good reviews on the products would likely not be there. I know–reviews aren’t always trustworthy, but I’m super picky and I’m telling you my honest experience.
Glycerin is also in most remineralizing toothpastes on the market. I can’t verify every positive reviews from those, but I think the science (and my results) speak for themselves.
You can of course opt to make your own homemade toothpaste (with or without glycerin) or your own homemade tooth powder.
So there you have it. Glycerin isn’t scary for the Tooth Fairy, or for us. In fact, it’s really your teeth’s good friend.
Glycerin is safe and non-toxic and likely beneficial for oral health. The myth that glycerin is harmful for your teeth is just that–an unverifiable myth. Having glycerin in your toothpaste is actually a good thing.
Acknowledgement: Big thanks to Stephanie of Bubble and Bee for her help analyzing the study mentioned in the post. I had hunches about quite a few of the points regarding that, but her assistance was very helpful. She’s a smart lady – and seems to have some great toothpaste too.