Face slugging is a trending skincare routine originating on social media which promises to give you a glowing and rejuvenated look by applying petrolatum, like Vaseline, on your face before bedtime.
Slugging takes its name because of the consistency of petroleum jelly, which is slimy as slug mucus, and has nothing to do with other skincare products containing actual snail mucin (slime) as active ingredient.
What is petrolatum (Vaseline – Petroleum Jelly)?
Petrolatum, also known as petroleum jelly or by the brand name Vaseline, is a very common ingredient in skincare which can be found almost everywhere, from lip balms, to face moisturizers, body lotions, hair and scalp conditioners, healing ointments, nail products, and more. Although being popularized only just recently on social medias, it’s been in the US Pharmacopeia since 1880 and has always been a well-known product in dermatologist practices.
Petrolatum is technically a byproduct of crude oil refining and a long-chain hydrocarbon; while this information may make you feel like it’s not good for the skin, it is actually not only a very effective moisturizing ingredient but also has wide applications in the treatment and management of many skin conditions like eczema and atopic dermatitis and is being ubiquitously found in dermatology textbooks; it’s employed in wound healing and surgical wound dressings where it is preferred to antibiotic ointments, and it is so safe that it is also routinely used in pediatric hospitals to treat skin conditions in newborn babies. It is a well-regulated and regularly tested product, so you shouldn’t worry about potential harmful contaminants.
Petroleum jelly is the most effective occlusive moisturizer ingredient, capable of reducing transepidermal water loss (TEWL) by 98-99% and thus greatly increasing the moisture content of both the epidermis and the dermis. Petrolatum is also good at restoring the skin’s main function, which is to be a mechanical barrier between the outside environment and the inside of our bodies, in those who have it compromised because of dry skin, harsh environmental conditions, or other reasons. Although it is commonly thought that Vaseline forms an impermeable layer on top of the epidermis, when rubbed onto the skin it actually doesn’t just sit there on top but liquefies and permeates the stratum corneum where it recrystallizes closing the gaps in between skin cells.
What products can be used for slugging?
Besides Vaseline, the brand name we all know and commonly refer to when talking about petroleum jelly, other brands market their own version of petrolatum with slight differences in formulation among the different products:
- Vaseline 100% Pure Petroleum Jelly / Original Healing Jelly by Unilever contains 100% petrolatum, while other products under the Vaseline brand name have formulations that include a wide range of ingredients.
- Aquaphor Original Ointment contains only 41% petrolatum, plus other occlusive ingredients like mineral oil and lanolin, as well as vitamin B5 (aka panthenol, promotes skin healing, reduces inflammation of sensitive skin, improves hydration, helps restore the skin barrier, …), glycerin which is a humectant meaning it attracts and binds to water, and other ingredients.
- CeraVe Healing Ointment contains 46.5% petrolatum, plus several other emollients, humectants and occlusives among the many ingredients.
Petrolatum in a minimum concentration of 5% reduces TEWL by more than 98% while other occlusive ingredients like lanolin, silicones like dimethicone, or mineral oil only reduce it by 20-30%.
What are the benefits of face slugging?
By greatly increasing skin hydration, face slugging improves the look of the fine lines and wrinkles caused by dry skin. This is just a temporary effect, but it can become permanent if the skin barrier is repaired over time solving the dry skin issue: the 1-2% TEWL that petrolatum allows for is actually fundamental to promote the restoration of the skin barrier function as completely blocking water evaporation from the skin does not allow for lipid and lamellar bodies biosynthesis and fibroblast migration impairing the skin’s ability to repair itself. The TEWL reduction by Vaseline boosts the repair processes while also temporarily acting as a substitute, or adjuvant, for skin barrier, meaning it will also protect the organism from the outside environment keeping bacteria and pollutants out. Dry skin has a rough look and texture which makes it a poor reflector of light, giving it a dull greyish color; by making it plump with petrolatum, the skin becomes smoother, more radiant and glassy looking just by enhancing the skin’s light reflection properties. Moreover, petroleum jelly can also improve other symptoms of dry skin, such as stinging or itching. Finally, the use of an occlusive that greatly increases hydration such as petrolatum causes an increase in the skin’s permeability, meaning drugs applied to the skin prior to Vaseline become more bioavailable and making in general active ingredients more effectively absorbed when applied before face slugging.
What is the correct way of doing the face slugging?
Vaseline is commonly applied at nighttime due to the generally non-pleasurable feel and look that this product has. Petroleum jelly should therefore be the last step in your night skincare routine:
- Start by cleansing your face with a cleanser. If you wear make-up during the day, start by removing your make-up.
- Apply other skincare products, like serums first. Be aware of the increased bioavailability caused by petrolatum (check risks paragraph below).
- If you suffer from very dry skin, or if the environmental conditions make your skin dry (ie. In winter due to cold and wind for example, in summer due to increased UV exposure and chlorine in pools, …), then it would be best to apply a humectant ingredient first or a combination of humectant and emollient ingredients to hydrate and aid the repair of the skin barrier.
- Finally, apply the petrolatum.
One trick to boost the moisturizing properties of petrolatum is to apply it over slightly dampened skin, which is when occlusive moisturizers have the most pronounced effect.
In some social media videos that made face slugging popular, an exorbitant amount of petrolatum is applied on the face: this is not needed, just treat it as any other cream or product you would use in terms of quantity; an almond sized portion should be enough to cover your face.
Rub it thoroughly on the skin to allow it to penetrate the stratum corneum of the epidermis and settle in. Don’t go to sleep immediately after applying petrolatum to avoid rubbing it off with your face on the pillow.
Who should not try face slugging?
Acne-prone individuals and those with oily skin type are generally advised not to try face slugging. While petrolatum is not a comedogenic ingredient, it may still cause break outs due to it locking it not just moisture, but also bacteria and sebum. Anecdotally, some people suffering from acne claim improvement in their condition, but this is what happens with general recommendations, they are generally good, but not always as we are all different and react differently. Ask your dermatologist for a tailored advice.
What are the risks and negative effects of face slugging?
Boosting the bioavailability of other ingredients layered below the petrolatum may sound good and captivating, but it could actually make them harsh so you should be cautious especially with ingredients like retinoids that are known to be aggressive in some individuals.
Decreasing the TEWL by more than 40% for long periods of time can lead to skin maceration and growth of bacteria, so it is best not to apply petrolatum 24/7.
A negative point about petrolatum is that it has a greasy feel, and most people don’t consider it pleasurable on their skin, moreover it can stain clothing so be aware of this especially if you plan on copying the Tik Tok videos where large amounts of petrolatum are applied (and wasted).
The take-away on face slugging and petrolatum
Petroleum jelly is an inert, nontoxic, nonirritating, and nonsensitizing occlusive ingredient which is widespread in all kinds of cosmetic products. Its use is nothing new in the dermatology field and its efficacy and safety have been long proven. Unless petrolatum is contraindicated in your specific case, this social media trend is definitely worth a try especially if you suffer from dry skin.
- Fitzpatrick’s Dermatology, 9th Edition
S Kang – McGraw-Hill Education, 2019
- Effects of petrolatum on stratum corneum structure and function.
R Ghadially – Journal of the American Academy of Dermatology, Mar 1992
- Role of Topical Emollients and Moisturizers in the Treatment of Dry Skin Barrier Disorders.
M Loden – American Journal of Clinical Dermatology, 2003
- Principles of Moisturizer Product Design.
C Lee – Journal of Drugs in Dermatology, Jan 2019
- The science behind skin care: Moisturizers.
Z Draelos – Journal of Cosmetic Dermatology, Apr 2018
- Active Agents in Common Skin Care Products.
Z Draelos – Plastic and Reconstructive Surgery Journal, Feb, 2010
- Cosmetic Dermatology – Products and Procedures, 3rd edition
ZD Draelos – Wiley-Blackwell, 2022
- Moisturizers: What They Are And How They Work.
CW Lynde – Skin Therapy Letters, Dec 2001
- Moisturizers: What They Are and a Practical Approach to Product Selection.
JN Kraft – Skin Therapy Letters, Jun 2005
- International Textbook of Aesthetic Surgery.
N Scuderi – Springer, 2016