You’ve probably heard of “slugging” recently, the viral practice of covering your face with Aquaphor, Vaseline, or any petroleum-based jelly on your face before going to sleep. It is called slugging because, well, you will look like a slug has slid across your face. Sound appealing? Believe it or not this practice has gained immense popularity in the past year. We decided to take a deep dive to figure out where slugging came from, and if it's actually helping your skin, the results might surprise you.
Where did Slugging come from?
Slugging first originated in South Korea, where women would cover their face in an occlusive petroleum product (most commonly, Vaseline) to “lock in” hydration and prevent trans epidermal water loss, a top contributor to dry skin.
Why Petroleum Jelly?
Petroleum Jelly (the “scientific” name for Vaseline and Aquaphor), is a byproduct of oil production. It is actually considered a form of crude oil, first discovered by oil rig workers who noticed the sticky substance coating machinery and at the bottom of empty oil barrels. Initially called “rod wax,” this substance was used by oil workers to protect their hands. Not exactly the most romantic way to discover a skincare product, but we’re not judging.
It should be noted that most petroleum jellies, like Vaseline, go through a rigorous refining process, to ensure they are “safe” to use on the skin of babies and adults alike. However, there are some people who speak out against the use of petroleum-based gels because they contain polyaromatic hydrocarbons (PAHs).
PAHS - the Good, the Bad & the Ugly
The dirty truth is, Polyaromatic hydrocarbons are classified as a carcinogenic ingredient. Exposure to polyaromatic hydrocarbons happens when we are near a car’s exhaust pipe, breathing in air from a wood fire or a candle burning, ect. Simply put, we are exposed to them nearly every day, in small quantities. However, studies have shown that polyaromatic hydrocarbons have been linked to cancers like breast cancer.
Most products in America that contain petroleum jelly are refined in a way that is safe for use. However, it should be noted that The US sets no requirements on refinement and the PAH content in the petroleum used in personal care products. Eek!
The EU has much tighter restrictions and requirements for cosmetic refining for PAH content, “The EU mandates that for cosmetic use, the full refining history of the petrolatum must be known and proven to be non-carcinogenic.” The US, doesn't.
The danger with PAH’s is that they have been linked to cancer, A study on Long Island, NY, found that those women with high levels of PAH-DNA adducts had a 50 percent greater risk of breast cancer. The formation of PAH-DNA adducts, an indicator of PAH exposure, is linked to cancer development. Don’t throw out your Vaseline just yet! As long as you are buying high quality petroleum products, you should be in the clear. However, It is important to note that the US does not require petroleum products to be vetted on their refinement process before selling. Before you slug, take a moment to research the product you are using and ensure that the factory it comes from is removing all possible PAH’s in their refinement process.
Another way to make sure your petroleum is safe? Ask the brand for their “USP”— the factory will have it and some brands, like Vaseline, indicate it on their packaging. If a brand is using “USP” petrolatum they meet or exceed the requirements set by the United States Pharmacopeia meaning it’s safe for food, drug, or medicinal use. However, the easiest way to determine the purity of your petroleum is via NDC listings and NDClist.com.
How People are slugging
The most common way to slug is to apply a layer of your jelly of choice to clean skin before you sleep. The idea is to let your skin “absorb” the jelly as you sleep, otherwise you might look a little funny walking around glowing from jelly in the daytime.
Most petroleum jellies act like an occlusive and a thick skin protectant, preventing water loss. Some water does escape, and this is a benefit. Totally sealing off your skin from the outside world would not promote lipid production. Fans of slugging state that petroleum jelly traps in moisture but lets enough out so your skin barrier repairs itself quicker overnight.
The Truth About Slugging
If you are determined to slug we recommend starting out with a clean face and adding an oil-based moisturizing serum underneath the jelly. This will make sure that you are locking in the serum and not trapping your skin under the jelly with no protection.
If you suffer from acne, we strongly recommend avoiding slugging. Slugging does not allow your face to “breathe”, and to naturally remove the dead skin cells and bacteria that your skin is trying to purge. If you have acne-prone skin sluggins can make your skin issues even worse by trapping your pores under an impervious layer of jelly.
To Slug, or Not to Slug
For many people who suffer from extremely dry skin, slugging might be a viable option that provides results. For most of us with skin that has breakouts and oiliness, slugging is not so beneficial. If you do choose to slug, be sure to make sure your face is clean as can be before applying the jelly. A face that has not been properly cleaned could be worsened by Petroleum jelly. And lastly, if you choose to slug make sure you are buying the highest quality jelly you can use. Many of us don’t realize that products like Vaseline are a byproduct of fossil-fuel production, and are a man-made product prone to impurities.
Behind every skincare trend, there is science, and we hope you enjoyed this piece on slugging, and what to be aware of if you are beginning your slug-journey!