Slugging, the practice of applying a thick occlusive product as the final step of an evening routine to prevent overnight moisture loss, became genuinely popular through social media for good reason: it works for dry and dehydrated skin. The catch, for people trying to avoid petroleum-derived ingredients, is that the original slugging product is Vaseline (petroleum jelly), which most natural skincare frameworks avoid.
The question is whether plant-based alternatives provide the same occlusive benefit. The answer is more nuanced than a simple yes or no.
What slugging actually does
The mechanism of slugging is simple: a thick, occlusive layer on top of your regular skincare routine physically prevents water from evaporating from the skin surface. Transepidermal water loss (TEWL) occurs continuously as water moves from the deeper skin layers toward the surface and evaporates. An occlusive seal dramatically slows this process overnight.
Petrolatum (Vaseline) is almost exclusively occlusive: it creates a near-impermeable barrier on the skin surface with essentially no water vapour transmission. Studies have shown that petrolatum reduces TEWL by up to 98%, which is far more than any other commonly available occlusive ingredient.
This extreme occlusion has limitations as well as benefits. It prevents water from escaping but also traps other substances under the seal. If you apply actives and then slug, the reduced evaporation and increased skin permeability under occlusion can increase absorption of those actives, which can be too much for some ingredients (like retinoids at higher concentrations).
Why petroleum-free options are less occlusive
No plant-based ingredient achieves the same level of occlusion as petrolatum. This is not a deficiency; it’s chemistry. Petrolatum is a complex mixture of long-chain hydrocarbons from petroleum that creates an essentially impermeable film. Plant-based waxes and butters have different molecular structures that allow more water vapour transmission.
This actually makes some plant-based options more suitable for many skin types. True petrolatum occlusion can cause milia (small white cysts) in some people, particularly those prone to congestion, because the near-complete blocking of the surface traps cellular debris. Less extreme occlusion from plant-based alternatives is often more comfortable and suitable for a wider range of skin types.
The most occlusive plant-based alternatives
Beeswax is one of the most occlusive plant-derived (or rather, animal-derived, since it’s from bees) natural ingredients. It forms a semi-permeable film with good water-barrier properties. Skincare formulations using beeswax as a primary occlusive provide good TEWL reduction, though not as extreme as petrolatum. Beeswax-heavy balms are among the most effective plant-adjacent slugging options.
Shea butter at high concentrations is a good occlusive. Its stearic and oleic acid-rich composition creates a solid, slow-melting fat at room temperature that sits on the skin surface and reduces water loss. Pure shea butter applied as the last step provides meaningful occlusion. Whipped shea butter with a lighter texture still provides benefit but with somewhat less barrier effect than dense, unwhipped shea.
Cocoa butter is similarly rich in stearic acid and creates an effective occlusive layer when used generously. The characteristic scent makes it less neutral than shea, which some people find appealing and others don’t.
Candelilla wax (from the Euphorbia cerifera plant, vegan) and carnauba wax provide harder, more film-forming alternatives to beeswax. They’re often used in lip products and balms for their strong occlusive properties and can be used in slugging applications in balm form.
Jojoba (a liquid wax rather than an oil) provides occlusion more than most oils, but its occlusive effect is mild compared to solid waxes and butters. It’s a reasonable light-occlusion option but doesn’t replicate heavy slugging.
Products designed for natural slugging
Dedicated overnight balms and sleeping masks in the natural beauty category are often formulated to provide the occlusive final layer for slugging without petrolatum. They combine plant waxes, butters, and sometimes silicone alternatives (polyglyceryl esters from plant sources) to create a sealing layer with appropriate texture.
Looking for formulations with shea butter, beeswax or candelilla wax, or cocoa butter high in the ingredient list gives you a product with genuine occlusive capacity. Products that are primarily oils with small amounts of wax added are less effective as slugging products because oils, while moisturising, don’t provide the same physical barrier that waxes and solid butters do.
Who benefits from slugging and how to do it with natural products
The most appropriate candidates for slugging: very dry skin, eczema-prone skin, those with a compromised barrier from over-exfoliation or harsh products, and those living in cold, dry climates where overnight TEWL is high. For northern European winters, the barrier-sealing benefit of a good occlusive last layer is genuinely meaningful.
The approach: complete your regular evening routine as usual, serums, moisturiser, any actives. As the very last step, apply a thin layer of your chosen plant-based occlusive, a hazelnut-sized amount of pure shea or a good overnight balm, pressed gently over the face. Sleep on it. Rinse or gently wipe excess in the morning if needed.
Don’t use a heavy, solid butter directly over prescription-strength retinoids without checking with your dermatologist. The increased absorption from occlusion can intensify the effects to an uncomfortable degree. With OTC retinol at standard concentrations, this is less of a concern.
The natural slugging approach won’t replicate 98% TEWL reduction, but 60-80% is still a meaningful improvement for dry and dehydrated skin, and the nourishing fatty acids in plant butters add genuine skin benefit that pure petrolatum doesn’t provide.