When I first started getting into Korean skincare I was dazzled by actives, extracts, and ingredients not found in Western skincare. It was all about the snail goo, and bird spit, and sheet masks, and figuring out just how hard I could hanbang, you know?
And now, a year later, it’s like holy shit have you heard about glycerin?!
Like, I’m super impressed with the most commonplace of ingredients.
But it’s just so easy to be when they’re impressive and my skin loves them. And really, a lot of times, at least the immediate effects you see from a product – the effects that make them pleasant and beneficial to use long enough for those fancy extracts to work – are from these workhorse ingredients.
And I realize that a lot of these ingredients that I’m just smitten with have been around for ages, and everyone and their brother has been tooting their horns about them, but it’s new to me and I’m excited so let me toot my horn too, okay?
So hey, fun fact: skin (and all cells of the body) have these things called “aquaporins”. What are aquaporins?
Aquaporins are integral membrane proteins that serve as channels in the transfer of water, and in some cases, small solutes across the membrane.
The part about “[transferring] small solutes across the membrane” is what’s really important here because one of those solutes is glycerin.
But before we get into that, a little information about glycerin:
Glycerin is a humectant that is present in all natural fats (though it can also be synthetically manufactured), and is also naturally found in skin. It, like other humectants, works by attracting water to the skin. In excessively dry climates or when used at concentrations of or near 100% that means it can end up drawing water from deeper layers of the skin and causing dehydration. But in mild climates, and as part of a formulation that contains emollients or occlusives, it helps create a protective barrier preserving skin hydration. It can also strengthen the skin barrier by improving barrier function, and increasing the thickness of your skin. (sources: x, x, x)
Sounds great right? Hang onto your pants because it gets better. Remember those aquaporins and glycerin’s ability to travel through them?
Glycerin was long known to have an effect on the skin that persisted longer than when the substance was present on the skin surface, which was labeled a glycerin reservoir. We now know that glycerin is transported through aquaporin channels, accounting for its superior moisturizing effects. As a result of this finding, high-concentration glycerin is being added to many moisturizers to function as a humectant, aiding in attracting water to the xerotic skin surface.
So even though you might wash off your product containing glycerin, enough of it has passed into you skin to help keep your skin moisturized.
HOW FREAKIN’ COOL IS THAT!?
You want to hear something else that’s neat? There is some evidence that glycerin helps cells mature properly:
In research published in the December issue of The Journal of Investigative Dermatology, Dr. Wendy Bollinger Bollag and co-author Dr. Xiangjian Zheng, who worked as a graduate student in her lab and is now a postdoctoral fellow at Vanderbilt University, show that glycerol also makes skin look and function better by helping skin cells mature properly.
The researchers’ findings about the signaling function of glycerol means the readily available fluid, found in its pure state on grocery store shelves and as a component of many other products, may help people with diseases such as psoriasis and non-melanoma skin cancers, that result from abnormal proliferation and maturation of skin cells, and may augment wound-healing.
Oh, and it’s also a very safe skincare ingredient:
In 2014, Cosmetic Ingredient Review evaluated available scientific data for glycerin, which demonstrated low oral and dermal (skin) adverse effects following single and repeated doses. In addition, data showed that there were no reported allergic skin reactions in human clinical studies.
In multiple laboratory reproduction and developmental safety studies, glycerin did not produce any adverse effects on parental reproductive capability or growth development, fertility or reproductive performance of their offspring. In a human fertility study of male employees who manufacture synthetic glycerin, who would be expected to be exposed to higher levels of the material, there were no differences observed in sperm counts or percentage of normally shaped sperm compared with a group who did not work with glycerin.
So with all those benefits is it any wonder the only ingredient used more frequently than glycerin in skincare and beauty products is water?