
Retinol, retinal, tretinoin, bakuchiol: a plain-English retinoid map
Retinoids are the most evidence-backed anti-aging category in skincare. They're also the most confusingly named. Here's the family tree.
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Retinoids are the most evidence-backed anti-aging category in skincare. They're also the most confusingly named. Here's the family tree.

Galactomyces ferment filtrate is the active behind SK-II's Pitera. The science is real and well-documented. The $185 price tag is not.

Snail secretion filtrate sounds like an internet joke. The clinical evidence is genuinely interesting. Here's what's in it, what it does, and…

Tea tree oil is real medicine and a real irritant. Most of the advice you'll find online about it is dangerous. Here's…

Rosehip oil is marketed as a miracle. The reality is more modest, and oxidation makes it tricky to actually deliver what the…

Glycerin sits quietly in almost every well-formulated moisturizer, doing the work people credit to hyaluronic acid. The case for the cheaper humectant.

Pre, pro, and postbiotics get labeled interchangeably, and most so-called probiotic skincare is actually postbiotic. Here's the difference and why it matters.

Vitamin C isn't a single molecule. It's at least seven, and the differences in stability, penetration, and irritation are bigger than the…

The AHA most people haven't heard of, and the one dermatologists keep quietly recommending for sensitive skin, acne, and skin of color.

EGCG, the active in green tea, is a strong antioxidant with documented skin benefits. The marketing oversells. The reality is reliably useful…