TikTok’s “Moisture Sandwiching” Trend Really Works, But Only If You Know *This*
If you’re unsure about what moisture sandwiching is or the best way to go about doing it, look no further. Derms weigh in. “A moisture sandwich refers to a technique of layering products that hydrate the skin to optimally moisturize the skin,” says board-certified dermatologist Marisa Garshick, MD. “The method specifically refers to applying ingredients to damp skin to help draw moisture in and then sealing it all in with a thicker moisturizing product, such as a cream or on ointment. In this way, it is best to layer the products from thinnest to thickest, using lightweight products first to ensure proper absorption and then heavier creams. There is an added benefit of applying products to damp skin as it can help to enhance penetration and also works to draw moisture in, especially when the product being applied is a humectant, such as hyaluronic acid or glycerin, which is known to attract moisture.”
Funnily enough, I started doing this before even hearing about the TikTok trend using my Evian Facial Spray ($23) because I found that it really helped my dry, barrier-damaged skin. As soon as I heard about the TikTok trend and received a bit of insight about it, I knew I was doing the right thing.
There’s another thing to consider, however, if you have a damaged skin barrier and want to try moisture sandwiching. According to board-certified dermatologist, Lauren Penzi, MD, the optimal water content for the stratum corneum (outermost layer of skin) is between 10% and 30%. Meaning, don’t go overboard and flood your skin with water before going in with your hyaluronic acid serum. If you go over that 30% mark, you might be hurting your skin instead of helping it. Carl Thornfeldt, MD, a board-certified dermatologist and founder of Epionce Skincare says to make sure you’re aware of this.
“Providing your skin with proper hydration is not as straightforward as TikTok makes it seem,” he shares. “If the skin barrier is healthy and intact, it will hold in moisture better. However, if the skin barrier is not healthy, adding more moisture won’t help in the long term. A healthy skin barrier has about 30% water. If you start going above and beyond that 30% mark with too much hydration, the skin barrier actually starts to break. Achieving healthy skin is not about having the highest amount of moisture, it’s about getting the skin barrier healthy so it can hold the amount of moisture needed to stay healthy.”
Thornfeldt isn’t saying that you shouldn’t hydrate your skin, of course. But he is saying that you should focus on incorporating ingredients that strengthen the skin’s barrier in addition to water-attracting ingredients like hyaluronic acid. Ceramides are really helpful for this as they help replenish essential lipids within the skin barrier.