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Can sunscreen reverse sun damage on its own?

A biochemist on how sunscreen lets your own biology repair sun damage, what the evidence supports. Plus whether you actually need it indoors, by your phone or computer, or when the UV index is zero.
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Does Your Skin Really "Absorb Everything"?
A cosmetic chemist on how little your skincare actually gets past the surface. Clean beauty, wellness, and whether a sunscreen causes cancer.
 • Marina | 4COMPLEXION
I'm a cosmetic chemist. Stop blaming 'pore-clogging' ingredients. Here's what really clogs skin, and how to clear it.
A biochemist's look at what really triggers clogged pores: sebum, dead skin, and formula behaviour, plus the evidence-based routine that keeps them…
 • Marina | 4COMPLEXION
No, Tretinoin Isn't Killing People. Reading the Papers.
A close look at the claim that tretinoin causes deaths, thins your skin, lets pollutants into your bloodstream, and is the same compound used in…
 • Marina | 4COMPLEXION
"Anti-ageing" creams won't fix menopausal skin. Here's what actually does.
A cosmetic chemist/biochemist's deep dive into the molecular biology of menopausal skin, the topical oestrogen evidence, and the protocol that actually…
 • Marina | 4COMPLEXION
Your "dark spot" serum won't fix those red marks. Here's what will.
A cosmetic chemist explains why post-acne red/purple marks are a blood vessel problem, not a pigment problem, and what actually fades them.
 • Marina | 4COMPLEXION
Your melasma serum isn't working. Here's why.
A cosmetic chemist breaks down the ingredients that work, the ones that don't, and why melasma needs a protocol — not a miracle serum.
 • Marina | 4COMPLEXION
When the Formula Becomes a Prop: A Cosmetic Chemist on What the Texture Trend Is Actually Costing Us
A professional opinion piece
 • Marina | 4COMPLEXION
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