The structure that keeps water in, and what happens when it stops
What the stratum corneum is made of, why transepidermal water loss explains most of what outdoor people feel, the three ways a barrier fails, and how long it takes to rebuild.
What the skin barrier actually is
The outer layer of skin is a physical structure with a job: keep water in and keep the outside out. What it is made of, how it is assembled and why that assembly explains almost everything.
Barrier · Structure · 10 minTransepidermal water loss, and why it explains almost everything
Water leaves your body through your skin continuously. The rate at which it does so is the single variable that ties cold air, wind, immersion and washing into one story.
Barrier · Water loss · 11 minWhat barrier damage actually means, physically
Damaged barrier is a phrase used to mean almost anything. There are three distinct physical failures behind it, they behave differently, and they need different responses.
Barrier · Failure modes · 10 minThe barrier repair cycle, and how long it actually takes
Skin rebuilds its outer layer continuously. Understanding what that process needs, and how slow it is, changes what you expect from a week of better habits.
Barrier · Recovery · 10 minSleep, recovery and the barrier's repair window
The overnight hours are the longest uninterrupted stretch your skin gets, and also a period of relatively high water loss. What that means in practice, without the wellness claims.
Barrier · Recovery · 10 minSurface pH, and what washing actually changes
Intact skin is mildly acidic, and that acidity is functional. What raises it, how long it stays raised, and why frequency matters more than any single wash.
Barrier · Washing · 10 minThis page contains no commercial links. There is no advertiser, no sponsor, no affiliate arrangement and no product placement anywhere in it. We name no brand and no product, here or anywhere else on this site, and we describe ingredient classes only by what they do. Published by Northbank Media. Our funding is set out in full on the about page.
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