What Does Glycerin Do For Your Skin? Derms Explain The Pros & Cons

You’ve probably seen glycerin listed on the ingredients label of many skin care products — and there is a good reason for that. It’s a known moisturizing ingredient that can help both the hair and skin in a number of different ways. But what makes glycerin so great and why does it seem to be in every moisturizer on the market? To get a complete breakdown of the hero ingredient, Bustle tapped Dr. Dendy Engelman, M.D., F.A.C.M.S., F.A.A.D., board-certified cosmetic dermatologist and Mohs surgeon Shafer Clinic, and Dr. Jeannette Graf, board-certified dermatologist and assistant clinical professor of dermatology at the Mount Sinai School of Medicine, to answer all of your questions.

What Is Glycerin?

According to Graf, glycerin is a type of humectant found in our bodies that pulls moisture from the top layer of the skin into the deeper levels to hydrate and keep your complexion moisturized throughout the day. While it’s most known as an ingredient in skin and hair care, you can also find it in other places. Engelman lists fermented foods like honey and vinegar as common places to find glycerin naturally and says that it may also be added to dried fruits and other foods.

In skin care specifically, glycerin is derived from plants, animal products, or petroleum, with the sole purpose of helping skin retain water. She explains that glycerin creates an occlusive barrier to prevent water loss and keep dryness at bay. An added bonus, she says, is that it is used to dress wounds as a way to prevent bacteria from entering and causing an infection.

How Is Glycerin Different From Hyaluronic Acid & Other Humectants?

Both glycerin and hyaluronic acid are humectants, which are moisturizing agents that retain moisture. The biggest difference between the two is their size. Graf explains that glycerin is a smaller molecule that can penetrate the skin more deeply, whereas hyaluronic acid is a larger molecule that mostly moisturizes the top layer of the skin. She adds that glycerin is recognized by the water channels in the skin (aquaporins) which makes it uniquely equipped to absorb more water.

Other known humectants such as lactic acid and amino acid urea also have exfoliating properties, which Engelman says makes them more likely to cause sensitivity compared to non-sensitizing glycerin.

Why Is Glycerin So Great For Your Skin?

As mentioned before, its main super power is keeping skin hydrated by minimizing water loss — but it does even more.

Graf says that glycerin can protect the skin from environmental irritants and has anti-aging benefits; because it keeps skin moisturized, it reduces the look of fine lines and wrinkles. Engelman previously touched upon its ability to create a protective barrier over wounds and adds that it can also heal dry, cracked skin. She also points out that while more research needs to be done, studies show glycerin is thought to soothe inflammatory skin conditions such as psoriasis and eczema.

How Do You Use Glycerin In Your Skin Care Routine?

It’s incredibly easy to incorporate into your routine as it is formulated into many products in the market. But Graf says it is best to use a moisturizer with glycerin as it will help keep skin moisturized and hydrated. “It will help lock in the moisture throughout the day,” she says. “Using it every day can help with dry skin conditions.”

Are There Any Side Effects?

Both experts say that glycerin has very minimal side effects if any at all. “Glycerin is a mild ingredient that is safe enough to be applied to open wounds,” says Engelman. “So its impact on the skin is mainly healing and moisturizing, with few unwanted side effects. It also plays well with other skincare ingredients.”

While glycerin is suitable for all skin types, Graf says that those with dry skin will benefit from it the most. Engelman also says that people with very oily skin should be wary of using too much of it, as it can trap excess oil and bacteria in the pores and cause breakouts.

Graf emphasizes that while the hydrating ingredient shouldn’t cause any irritation or sensitivity, always do a test strip on your skin anytime you introduce a new ingredient or product to your routine. “Everyone's skin is different and can react differently to a product.”

How Long Does It Take To See Results?

While Engelman says that glycerin can immediately help the skin feel calmer and more hydrated (especially when used on injuries or dry, cracked skin), Graf says it can take up to six weeks to see any major results when using it regularly. “It takes time for your skin to get used to and change when a new ingredient is introduced to your skincare routine,” she says.

You can tell that glycerin is working if you notice your skin looking brighter and more hydrated. As keeping your skin moisturized also helps reduce the appearance of fine lines, Engelman says that regular use of glycerin will cause the skin to appear plumper, dewier, and healthier.

More Information About Glycerin

Though Graf says it’s best used as a moisturizer, it is safe and beneficial to use it as a serum as well. “When considering how to add glycerin to your skin care routine, it is best to think about what you want to achieve with this ingredient,” says Engelman. “If the goal is to support and maintain hydration throughout the day, a serum is a great choice as it will be absorbed and can sustain layering other skin care ingredients on top. If the goal is to heal or prevent moisture loss, a thicker, more occlusive cream may be well-suited.”

Because of its minimal side effects, she adds that glycerin is safe to use every day. “Just be aware of your individual skin type and concerns,” she says. “Make sure to use glycerin in a way that best supports your skin’s health.”

Experts:

Dr. Dendy Engelman, M.D., FACMS, FAAD, board-certified cosmetic dermatologist and Mohs surgeon at the Shafer Clinic.

Dr. Jeannette Graf, M.D., board-certified dermatologist and assistant clinical professor of dermatology at the Mount Sinai School of Medicine.

Studies referenced:

Widyarman, A., Drestia, A., Bachtiar, E., Bachtiar, B. (2018). The Anti-inflammatory Effects of Glycerol-supplemented Probiotic Lactobacillus reuteri on Infected Epithelial cells In vitro. Contemp Clin Dent. 2018 Apr-Jun;9(2):298-303. https://pubmed.ncbi.nlm.nih.gov/29875577/