Water molecules have one of the strongest familial-like bonds that are tough to break—though not as strong as the bond between Jonah Hill and James Franco. Because of this bond, when these water molecules evaporate from the surface of your skin, they pull out with them other water molecules that are existing deeper down in your skin. Meaning, as water sitting on top of your face evaporates, it actually dries out your skin, not hydrates it.
This is called Transepidermal Water Loss or just TEWL for short.
Our bodies are losing water all the time. On average while sweating, people can lose around 2-4 liters of water. We sweat when we're exerting energy, however, water vapors can leave our bodies on their own as well. Water vapors leaving our bodies is also dependent on the strength of our skin's barrier.
“How do I prevent TEWL” you ask?
It’s pretty easy actually. After you get out of the shower or cleanse your face with your Solid Face Wash, simply pat (don’t wipe!) your face dry—it’s always best to gently pat your face because your face can be sensitive and towels can be rough.
You can slow down the amount of water leaving your skin by keeping hydrated AKA drinking more water as well as using a humidifier in your room at night. People living in more humid climates are fortunate enough to have humidity provided by their local weather system—who cares about hurricane season when you can have hydrated, supple skin?
People living in dry or colder climates where the air lacks moisture are more susceptible to dry skin.
After cleansing your face, use a daily moisturizer like your Face + Eye Cream—this will give your skin the moisture it needs by helping to keep water from leaving your skin. On average our bodies can lose around 300 to 400 ml a day through TEWL. It's important to maintain a healthy skin barrier in order to not only retain water but also noting the idea that the health of our skin barrier can also be an indicator of overall health.
Just to recap, water vapors leave our body in a process called Transepidermal Water Loss or TEWL. This is directly affected by our skin's barrier and its ability to retain water. Moisturized skin is better equipped to retain water and slow TEWL compared to dry skin and all you have to do to have moisturize healthy skin is to... moisturize and stay hydrated!