Retinol at 25 vs. 45: A Side-by-Side Look at What Changes and Why It Matters
Retinol is one of the few skincare ingredients with a genuine body of clinical evidence behind it — over 40 years of dermatological research, starting with tretinoin studies at the University of Pennsylvania in the 1980s. But “retinol works” is not the same as “retinol works the same way for everyone at every age.” Skin … Read more