Vegetable Glycerin: Derms Explain The Skin Care Benefits & How To Use It Properly
When you hear the term vegetable glycerin, soft, supple, hydrated skin probably isn't the first thing to come to mind. In fact, you might even consider it a worthy ingredient for your next baked good recipe. But we're here to set the record straight: Vegetable glycerin is one of the most commonly used humectants on the market, and chances are, you're already using it without even knowing it.
Here, we tapped board-certified dermatologists to get the scoop on vegetable glycerin: what it is, how it benefits the skin, and how to use it properly.
What is vegetable glycerin?
"Also called glycerol and glycerin, vegetable glycerin is a water-soluble sugar alcohol that comes from a variety of plant oils, including soy, palm, coconut, and corn," says board-certified dermatologist at Marmur Medical Rachel Maiman, M.D. "It's made by heating triglyceride-rich vegetable fats under pressure or combined with a strong alkali." Animal-derived glycerin, on the other hand, comes from animal fats.
This heating process causes the glycerin to separate from the fatty acids and, mixed with water, forms an odorless, syrup-like liquid. But before you think about adding this syrupy potion to your meals, you should know that vegetable glycerin is uber-hydrating for the skin. In fact, it's commonly used in skin care products to give you that soft, supple, dewiness you've dreamed of (more on this later).
While vegetable glycerin and animal-derived glycerin have similar benefits, the notable difference between the two is that vegetable glycerin is always plant-based. "Glycerin is a general term for a type of sugar alcohol compound, which can be derived from either animal fats or plant fats," Maiman says. "It can also be artificially synthesized in the lab." (You also have a natural supply of glycerin in your body, which decreases over time; this is why many brands incorporate it into their products.)
Even though glycerin and vegetable glycerin can be used interchangeably, a brand that uses the vegetable-derived ingredient will likely make it clear on the label. If you're not sure, look for vegan formulas, or feel free to ask the brand directly about how they source their glycerin.
Benefits for skin.
Now that we know what vegetable glycerin is, let's discuss what makes it a skin care hero:
For starters, glycerin is a humectant. And if we're being honest, almost anyone can benefit from adding more humectants to their routine. "Humectants are basically 'water magnets,'" board-certified dermatologist Ava Shamban, M.D., founder of SKINFIVE, tells mbg about the ingredient category. "They work to help pull moisture from the air into the upper layer of your skin to keep the skin cells hydrated, plump with a firmness and bounce." In fact, one study found that using a cream infused with glycerin better hydrated the skin than a cream with silicone oils or hyaluronic acid.
However, it's important to know that in order for a humectant to work, it has to be used with emollients and occlusives, says board-certified dermatologist Hadley King, M.D. "Emollients are saturated and unsaturated variable-length hydrocarbons, which help in skin barrier function, and occlusives are oils and waxes which form an inert layer on the skin and physically block transepidermal water loss." So, yes, glycerin is a lovely humectant, but you need a combination of all three categories to effectively draw in water, strengthen the skin barrier, and keep all that hydration locked inside.
It supports a healthy skin barrier function.
"Glycerin is often formulated in products that are designed to sit on the surface of the skin and protect the skin's natural barrier," King says. Having a healthy skin barrier helps to protect against moisture loss and can even help to protect against irritants and environmental aggressors1. Board-certified dermatologist Raechele Cochran Gathers, M.D., agrees: "Along with hydration, glycerin helps with improving the function of the skin barrier, which helps prevent the loss of water, protecting the skin from irritation and improving wound healing in the skin," she previously told mbg.
In short, healthy skin starts with strong skin barrier function, and glycerin can help you build up that barrier.
It soothes inflamed skin.
Thanks to its hydrating and skin-barrier-supporting abilities, vegetable glycerin is a great ingredient for those with inflammatory skin conditions. "Moisturizers with glycerin can be especially helpful in people with eczema," says Cochran Gathers. Not to mention, glycerin plays nice with a host of other ingredients and buffers their potency, which can make those products more tolerable for sensitive complexions.
While we need more research on its anti-inflammatory properties specifically, vegetable glycerin may have some soothing properties as well: "Studies have shown that glycerin exerts antimicrobial effects2 and is capable of reducing the production of cytokines involved in most inflammatory and irritant responses in the skin," Maiman says. Another study found that mice treated with glycerin had fewer white blood cell responses to irritants.
Are there any warnings or side effects?
Short answer? No, not really. Maiman says any ingredient allergy is technically possible, but side effects from vegetable glycerin are rare. "Vegetable glycerin is generally well-tolerated by most, including those with sensitive skin," she says. Of course, you should always patch-test before slathering on a new ingredient, just in case you do face a reaction.
And for those who stick to vegan skin care, we suggest checking your labels to make sure your glycerin is, in fact, plant-based. Again, brands that use vegan formulas will likely make it clear on the label, but you can always double-check if you aren't sure about their glycerin in particular.
How do I use vegetable glycerin in my skin care routine?
Chances are, at least one product in your current skin care routine is formulated with glycerin. "Glycerin is such a prevalent ingredient that there's a very high likelihood it's in whatever moisturizer you're using," Maiman says. But to optimize its effects, there are a couple of things you can do:
- First, as we mentioned above, combine glycerin with an emollient and/or occlusive. This is key to reaping its hydrating benefits. Now, many skin care products are already formulated with a combination of humectants, emollients, and occlusives, but it's important to keep in mind if you're using a humectant-only serum. Once you apply your favorite glycerin-infused product, top it off with an emollient-based serum or an oil to lock all that hydration into place.
- Maiman also recommends applying glycerin products to damp skin. "This gives the humectant property its best shot at grasping onto water," she says. (Remember: Humectants are water-loving, so you want to give them the water they need to do their job properly.) "In a similar vein, it can also be applied post-shower in a room that's steamy, allowing glycerin to optimally lock onto atmospheric water," Maiman adds.
Vegetable glycerin is a plant-based hydrator that is likely found in your favorite moisturizers, thanks to its humectant properties. It's generally well tolerated by most—sensitive skin included—and it's most effective when paired with an emollient or occlusive.
Andrea Jordan is a beauty and lifestyle freelance writer covering topics from hair and skincare to family and home. She received her bachelor's in Magazine Journalism from Temple University and you can find her work at top publications like InStyle, PopSugar, StyleCaster, Business Insider, PureWow and OprahMag. When she's not writing, you can find Andrea tackling new recipes in the kitchen or babysitting one of her many nieces and nephews. She currently resides in New Jersey with her husband and cat, Silas.