Healthy skin is hydrated skin. But staying properly hydrated requires more than just drinking your eight glasses a day, because your skin is constantly losing moisture — even right this second. But how does skin actually lose moisture? We get into that and more, as well as everything you need to know about how to keep your skin happy, healthy, and hydrated.
what’s transepidermal water loss, and why does it matter?
Skin loses moisture through a process called transepidermal water loss; this is when moisture seeps out through your epidermis and evaporates. The good news? It’s totally normal. The bad news? Your skin *really* needs that moisture. Without it, your skin may feel dry and rough and look slack or dull. Wrinkles and lines may also appear deeper when skin doesn’t have enough moisture.
While transepidermal moisture loss occurs naturally, certain factors can make it worse. Cold, dry weather can sap moisture from skin, for one, which is why skin may get duller or drier in the winter. Research also shows that your skin barrier is more permeable at night, which allows for a higher rate of transepidermal water loss while you sleep. (Blame your circadian rhythm for this one!) And last but not least, anything that weakens your skin barrier, such as overwashing or exfoliating too harshly, can allow moisture to escape more easily — that’s why it’s so important to keep your skin barrier intact. Speaking of…
what’s the skin barrier?
Your skin barrier is the first line of defense against everything from environmental aggressors like pollution to viruses and microbes. It consists of three layers, which all work together to keep good things in (e.g. moisture) and bad things out.
First up is the microbiome, which is slightly acidic and consists of bacteria that naturally live and thrive on the surface of your skin. These good bacteria keep the harmful microbes and fungi in check.
The acid mantle
Beneath the microbiome is the acid mantle. This layer is slightly acidic — as the name implies — and consists of sweat and sebum secretions. Basically, if you’ve ever heard talk of your skin’s “natural oils,” this is them. The acidity levels of both the microbiome and acid mantle are key here, as that acidic environment helps inhibit the growth of acne-related bacteria.
The lipid barrier
Finally, beneath the microbiome and acid mantle lies the lipid barrier, which is the protective moisture barrier that makes up the third layer of your epidermis. It’s primarily made up of lipids, including fatty acids and their derivatives, and in charge of keeping moisture within your skin.
When any layer of the skin barrier is weak, things can pass through it more easily — including moisture. Therefore, it’s essential to keep it resilient, which might require making a few tweaks to your routine.
how to minimize moisture loss and strengthen your skin barrier
Use pH-optimized skincare
A slightly acidic pH is essential for a healthy skin barrier, and anything that throws off the pH can weaken it. When you suds up, do so with a cleanser that leaves your pH slightly acidic — with neutral being 7 — such as our oil to milk cleanser, We also recommend using a pH-optimized toner — our rosewater toner has a pH of ~5.5, while raspberry vinegar toner clocks in at ~4.
Load up on antioxidants
Antioxidants, such as vitamins C and E, are winners for both protecting against and repairing skin damage. They run interference against free radicals, which are skin-damaging molecules released by environmental aggressors like pollution and sun exposure. In doing so, they keep your skin barrier safe and sound. You can find them in matcha, beetroot, chlorella, ginger, maca, and pomegranate, among many other superfoods.
Moisturize, moisturize, moisturize
Your skin needs to drink up moisture to offset ongoing transepidermal water loss. Plus, your lipid barrier itself benefits from having its fatty acids replenished. That’s where our new matcha face moisturizer comes in. It contains pomegranate seed oil and matcha tea powder — both rich in antioxidants — as well as fatty acid-rich green tea extract to reduce water loss, fortify your skin barrier, and deliver deep hydration. Fun fact: Our green tea extract is actually derived from the layer of fatty lipids found on the surface of green tea leaves. These seal in those antioxidants and help keep moisture from escaping for all-day hydration.
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