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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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What actually has trial evidence for photoaging — retinoids, sunscreen — and how to start without wrecking your face.

Anti-aging routine templates Honest results timelines Retinol Vitamin C Bakuchiol

Actives
Starting retinoids without wrecking your face
The most-proven active in skincare is also the most-quit. A low-drama onboarding plan: dose, frequency, buffering, and what week three is supposed to feel like.
June 21, 20264 min readUpdated Jul 2026
Actives
Retinoids: the most-studied anti-ager, and what "tretinoin" actually proved
Retinol, retinal, tretinoin — the vitamin-A family is the closest thing skincare has to a sure thing. Here's the trial that started it.
June 11, 20262 min readUpdated Jun 2026
Sun care
Does sunscreen actually prevent skin aging?
Not a marketing claim — a randomized trial followed people for four and a half years.
June 10, 20261 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