
The science behind PM-only retinoids, and the rare daytime exceptions
Retinoids photoreact and the degradation is real. The biochemistry behind their PM-only label, the photostable exceptions, and how to apply the rule…
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Retinoids photoreact and the degradation is real. The biochemistry behind their PM-only label, the photostable exceptions, and how to apply the rule…

Bakuchiol is marketed as the pregnancy retinol, but the safety data isn't complete. We summarise what's firmly known and where the evidence…

Centella is anti-inflammatory but it isn't a steroid. We compare what each ingredient does and the conditions where one cannot substitute for…

Some SPFs do cause breakouts but it isn't because they're sunscreens. We sort filter chemistry from formulation choices behind acne flare-ups that…

The internet says you must layer water over HA or it dries out your skin. We dug into the lab data, and…

If your sheets have yellow patches, your serum may be the culprit. We explain the oxidation chemistry behind staining and how to…

Salicylic acid isn't universally off-limits for sensitive skin. We cover the four percentages, two pairings, and conditions that make it safe (or…

Cold air, retinol, and a stripped barrier can feel like thinning skin. The truth is the opposite. Here's the cellular science and…

Niacinamide doesn't speed cell turnover, so it technically can't purge. We explain what those breakouts actually are and how to manage them…

Peptides are sold as a plumping miracle. We separate what the research actually shows from the marketing language used on most luxury…