ABOUT
Hi, I'm Rolf.
I got frustrated with skincare advice that was based on marketing instead of evidence. So I started reading the clinical trials myself — and sharing what I found, including when the popular answer turned out to be wrong.
The problem I kept running into
The skincare industry spends billions on marketing and almost nothing on honest product comparisons. Most "best product" lists are based on marketing partnerships, not on anyone testing whether the products work.
Meanwhile, clinical trials comparing ingredients exist — hundreds of them. But they're buried in medical journals, written for researchers, and almost never translated into advice you can use.
How I work
I find and analyze clinical studies that compare skincare ingredients — extracting effect sizes to show not just whether something works, but how much more it works than the alternative. I also spend a lot of time in Seoul, where I've been going since 2017, and I bring back what I learn from Korean skincare.
Not everything I recommend comes from a clinical trial. Some of it comes from years of personal testing, conversations with Korean dermatologists and pharmacists, and simply paying attention to what works. When something is backed by strong research, I'll tell you. When it's my personal experience, I'll tell you that too.
Why I started this
I spent years doing what most people do: guessing. Buying products based on marketing claims, layering serums based on influencer routines, and wondering why my skin kept getting worse.
When I finally dug into the research, I found a disconnect between what the science showed and what the industry sold. Products with strong clinical evidence were often inexpensive and unglamorous. Products with beautiful packaging and celebrity endorsements often had no rigorous testing behind them at all.
My career has been built on one question: what matters more? I asked it as a PhD researcher. I asked it as an early-stage investor. And I asked it standing in a Seoul pharmacy, holding two serums with identical ingredients and a forty-dollar price difference. This site — and the book, Skin Overdraft — is what I found.
What I'm building
A map of what actually matters in skincare — ranked by how much more one thing outperforms another. The evidence catalog, the book, the newsletter, the live streams — they all feed the same question: what matters more than what, and by how much?