Editor’s Note: Holly Thomas is a writer and editor based in London. She is morning editor at Katie Couric Media. She tweets @HolstaT. The opinions expressed in this commentary are solely those of the author. View more opinion on CNN. CNN  —  Adolescents’ enthusiasm for beauty products is nothing new. Indeed, we’ve long taken it for granted. When I was about 12, I received a large — unsolicited — Estee Launder makeup sampler for Christmas. The box felt like a totem of my impending maturity, recognition that I would soon be allowed access to an as-yet out-of-reach club. I gave it pride of place on my bedroom table (swiftly rebranded as a “dresser”…