Get to grips with glycerin – from what it does to how to use it and what to avoid – in our latest skincare Ingredient Spotlight
Glycerin is one of the most frequently used ingredients in cosmetics and skincare products. In fact, you’d be hard-pressed to find many brands and products that don’t contain this so-called wonder ingredient.
Often referred to as glycerol, glycerin is what’s known as a natural skin hydrator. It helps to moisturise your skin, keep it hydrated and give your complexion a healthy, dewy glow.
Given the fact it’s a natural compound, glycerin is safe to use for all skin types and it also pairs well with other skincare ingredients without causing irritation – as long as it’s not used in its pure, undiluted form (we explain more below.)
Read on to find out more about glycerin from what it does to how it works, how to use it, and what to avoid. This guide is the latest in our Ingredient Spotlight series where we attempt to demystify the art of understanding what the many, many ingredients in skincare and makeup do.
Glycerin is an odourless liquid that has a sweet, syrup-like consistency. It’s been used in skincare, haircare, and other products for more than 50 years. It comes from glycerol, which is a type of fatty sugar alcohol that plays a number of roles in the body.
In fact, glycerol and glycerin have the same chemical makeup but glycerol is the name of the pure form of the compound, while glycerin is the name used for any product that contains at least 95% glycerol.
When you eat food that contains fats, your body breaks them down into individual components, which includes glycerol and fatty acids. The glycerol is then converted into glucose by the liver, which the body can use for energy.
Yet glycerol also helps to regulate the body’s water balance. It’s a component that’s found in the fluid around your cells and plays a role in helping to maintain water in your body’s tissues. It also acts as a “humectant”, which means it attracts – or is a “magnet” for – water from the air, or within the skin to increase hydration.
In fact, glycerin is “the most effective humectant” skincare ingredient, according to scientific research. More effective than fellow humectant hyaluronic acid, as well as alpha hydroxy acids, and propylene glycol.
FURTHER READING: The truth about the acids lurking in your skincare – from hyaluronic, to glycolic, lactic and salicylic
Glycerin works by pulling moisture from the air into your stratum corneum (the outer layer of your skin) and due to having a low molecular weight it draws moisture to the deeper levels of your skin.
Glycerin also works as an occlusive, which creates a physical barrier on your skin to prevent water loss and by doing so locks in hydration. Glycerin remains in your skin a while after application which means it also helps to protect your skin barrier from environmental aggressors, such as pollution.
Glycerin provides a number of skincare benefits. It:
Improves hydration: With its ability to reduce moisture loss and increase moisture intake for your skin, glycerin helps to relieve dry skin and heal damaged skin. Working alongside emollients and oils it makes dry skin feel soft and subtle. That’s why glycerin is also a great ingredient to help with psoriasis.
Reduces fine lines and wrinkles: As well as boosting the health and structure of your skin, glycerin makes your skin appear plumper, making your fine lines and wrinkles less noticeable. Glycerin does this by increasing the water volume between cells to give your skin a fuller, firmer appearance. Collagen is the protein that gives your skin its elasticity and glycerin helps to bind and stabilise your collagen, meaning this too helps to make your skin appear more youthful.
Repairs and protects the skin barrier: In addition to improving hydration, glycerin helps keep the lipids between our skin cells healthy. This helps to protect against irritation, and repair the skin barrier.
Balances oily skin: Even oily skin needs hydration yet some hydrating ingredients can clog pores. Glycerin for oily skin works well because it doesn’t clog your pores. Glycerin is also a great ingredient for sensitive skin because it’s natural and therefore gentler to the skin.
Boosts the efficacy of other skincare products: Glycerin also works as a great friend to other ingredients in your skincare products because it enhances the penetration of other ingredients (particularly the absorption of other topical ingredients) into your epidermis (the top layer of your skin).
With dehydrated skin being the main cause of fine lines and wrinkles, itchy and dry skin, as well making skin appear dull, you can see why glycerine is a fantastic ingredient for skincare products. By being a natural ingredient, glycerin is also less harsh to the skin than some other ingredients that do a similar job. It also doesn’t strip your skin of its natural oils and moisture.
@victoria_woolly_web Considering how many products I’ve already tested contain glycerin, it made sense when a few of you requested I try it on its own. The increase was good, not great; it could be that I didn’t use much (relatively) as it’s hard to control the flow. I’m planning to test different % of glycerin so I’ll be able to see how that all works out with those follow-up tests. Applied to damp skin #mamabella #naturalskincare #naturalskincareroutine #glycerin #hydration #hydrationnation💦 ♬ Green Green Grass – George Ezra
FURTHER READING: Do you have dry skin or is just dehydrated? Here’s how to tell the difference
Whether glycerin is vegan or not depends on the type of glycerin used. If it’s vegetable glycerin, it’s vegan and comes from vegetable origins like soya, coconut oil, or palm oil. Animal-derived glycerin usually comes from animal tallow, which is a rendered form of mutton or beef fat.
The problem is, it’s not always easy to tell from looking at the label alone. If a product says it’s vegan-friendly then it’s usually safe to assume it uses vegetable glycerin. That’s not to say that if it’s not listed as vegan then it must contain animal glycerin. It’s a bit of a minefield so if you’re unsure, we recommend that you contact the brand to ask.
Despite the fact that glycerin (and glycerol) are natural compounds, dermatologists warn against it on its own. Certainly not without diluting it first. This is because undiluted glycerin has been known to irritate the skin.
If you’re looking to add glycerin to your skincare routine, introduce it in a product where it’s already been mixed with other ingredients.
Often you can tell if a product includes glycerin because it’s thicker and typically stickier than those without. This is certainly the case if the product lists glycerin high up in the ingredient list. All ingredients in skincare and makeup are listed in terms of volume. That means that each formula contains more of the ingredients at the top of the list and less of the ingredients at the bottom.
For example, if aqua/water is listed as the first ingredient, that product’s formula contains more water than any other ingredient.
If you’re looking to get the most benefit from glycerin in your skincare, opt for products where glycerin is listed higher up. If you want to add glycerin, but don’t like sticky or thick creams and serums, look for products where glycerin is further down the list.
FURTHER READING: Skincare ingredient checker: Get to grips with what’s in your skincare with our ingredients guide
You can buy all sorts of products containing glycerin including (but not limited to):
Below we’ve highlighted the best glycerin for skin products in each category.
£13.50 | Buy now
La Roche-Posay Toleriane Dermo-Cleanser is a gentle, fragrance-free cleanser that’s great for all skin types, including sensitive skin. It emulsifies nicely and removes dirt, makeup and other impurities while maintaining the skin’s natural moisture barrier.
The main active ingredient in the Toleriane Dermo-Cleanser is glycerin but it also contains soothing agents like niacinamide and ceramide-3.
These work to calm and protect the skin from irritation.
To use the cleanser, mix a small amount with water and massage gently into your face and neck in a circular motion. Rinse thoroughly with water or remove with a cotton pad. The Toleriane Dermo-Cleanser can be used morning and night as the first step in your skincare routine.
FURTHER READING: How to layer skincare: Knowing the best skincare order will help make the most of your products
Buy now from Boots
£50.50 | Buy now
Very few brands reveal how much of each ingredient is in their products but some make the odd exception. This is the case with Kiehl’s Hydro-Plumping Re-Texturizing Serum Concentrate.
Formulated with 15% glycerin – glycerin is the most abundant ingredient in the serum behind water – this serum helps improve the appearance and texture of dry and dull skin.
In addition to glycerin, it contains hyaluronic acid, red algae, and plant-based glycoprotein. All of which help to improve the skin’s texture and elasticity, plump-up fine lines and wrinkles, and leave the skin looking and feeling more youthful and hydrated.
If this serum is too expensive, then we also recommend the Good Molecules Hyaluronic Acid serum. Despite its name, this serum actually only contains 1% hyaluronic acid but does contain 3% glycerin which combines to make a super hydrating alternative to Kiehl’s version.
Good Molecules is an American brand but it ships to the UK and even when you factor in delivery, paying just $6 for this serum means you’re still saving a hefty sum. What’s more, as part of our large-scale best serum group test, the Good Molecules serum beat off competition from a lot of other expensive rivals, too.
Buy now from Boots
£10 | Buy now
Not too dissilmilar to the Kiehl’s serum, Cetaphil’s Daily Hydrating Moisturiser contains glycerin, hyaluronic acid and so-called natural moisturising factors (NMFs) found naturally in the skin to hydrate, prevent moisture loss and protect the skin’s moisture barrier.
It’s been specifically formulated to be hypoallergenic and gentle for sensitive skin, while also not clogging pores or causing breakouts.
In our major group test in which we look for the best moisturiser, the Cetaphil Daily Hydrating Moisturiser increased the hydration of our skin by an impressive 20% in just five minutes. If you want to know more about this group test, head to our best moisturiser page.
Buy now from Boots
Victoria is founder and editor-in-chief of mamabella, freelance journalist and Mum. She has a passion for empowering people to feel beautiful whatever their age, size, skin type and budget