Hey Reader!

Have you ever tried to “fix” winter dryness by slathering on more moisturizer… only to wake up feeling just as tight and flaky? You’re not imagining it. And you’re definitely not alone.

Every winter, millions of people follow advice that sounds logical but actually makes dehydration worse. It’s no wonder your barrier ends up confused and overwhelmed.

There are so many myths about TEWL, and today, we’re making sure you never fall for them again.

MYTH #1: “If your skin is dry, just use more moisturizer.”

Truth: A moisturizer can help comfort the skin, but it doesn’t automatically stop water from escaping.

In cold, low-humidity environments, Transepidermal Water Loss (TEWL) rises. That means water is evaporating from your skin into the air more quickly than usual. Adding more moisturizer doesn’t fix the underlying issue: the barrier needs reinforcement to slow that water loss.

To actually feel hydrated, your skin needs a combination of:

• Humectants to pull water in
• Emollients to soften and support the barrier
• Occlusives to slow evaporation

Relying on moisturizer alone often leaves skin thirsty again within hours.

MYTH #2: “Tight skin after cleansing means it’s really clean.”

Truth: Tightness is a sign your barrier has been disrupted.

When a cleanser strips away essential lipids, the skin loses part of the protective film that keeps hydration in. This immediately increases TEWL, which is why that “squeaky clean” feeling quickly turns into dryness or irritation.

If your skin feels tight after washing, it’s not a good sign.
It’s your skin saying: “I need gentler cleansing and better barrier support.”

MYTH #3: “TEWL doesn’t matter — dryness is just part of winter.”

Truth: TEWL is the core reason winter skin feels tight, flaky, or sensitive.

Cold weather, wind, and indoor heating all accelerate evaporation from the skin.
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When TEWL rises, it affects:

• Hydration levels
• Glow
• Comfort
• Fine lines
• Sensitivity
• Overall barrier health

Understanding TEWL isn’t about jargon. It’s about why winter dryness happens in the first place and how to regain control.

How to Support Your Barrier and Reduce TEWL This Season

A winter routine that protects hydration should focus on:

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✔ Gentle, non-stripping cleansing​
✔ Hydrating ingredients that bind water to the skin​
✔ Barrier-supporting moisturizers​
✔ Occlusives when humidity drops​
✔ Seasonal adjustments instead of summer-style routines

Small changes here make a big difference in how your skin feels day to day.

👉 Learn the science behind TEWL and why winter hydration is different

Want To Learn Even More About The Science of Skincare?

Check out these other articles on RelatableSci.com that break down the science of skincare a little more.

Do you want to read past newsletters? Head over to the archive of all of our previous newsletter series.

​Relatable Skincare Report Archive​

Stay tuned for my next email. And if you found this interesting, share it with a friend! And if a friend sent this to you and it was helpful, subscribe so that you get it delivered to your inbox next week, and a free routine audit guide to say welcome!

​Subscribe and Get the Free Skincare Routine Audit Guide​

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Hit reply and tell me: What’s your biggest winter hydration struggle?

Wishing you a great week,

Allie

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