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Evidence-based skincare

Plain-language explainers, each grounded in the study behind the claim. We cite our sources and stick to what the research actually measured.

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Reactive skin usually starts at the barrier. How to repair it, test products safely, and pick gentler versions of the actives.

Gentle routine templates Introducing products safely Centella (cica)Ceramides Squalane

Skin barrier
Barrier repair 101: what it is, how it breaks, how it heals
Stinging moisturizer, sudden sensitivity, tight flaky skin — half of skincare trouble is a damaged barrier. What that means physically, and the boring routine that fixes it.
June 20, 20263 min readUpdated Jul 2026
Skin barrier
The skin barrier, and why ceramides matter
Half of skincare problems trace back to a leaky barrier. Here's what that means and what the evidence says about repairing it.
June 14, 20262 min readUpdated Jun 2026
Actives
Bakuchiol vs. retinol: does the "natural retinol" hold up?
Bakuchiol gets sold as a gentler retinol. One head-to-head trial actually put them side by side.
June 16, 20262 min read