Have You Heard of the 12-Week Rule For Testing New Skincare Products?

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Last week, I told you guys about my extremely boring but effective skincare routine. (ICYMI: It involves just three steps: cleanse, treat and protect.) This week, I’ll share how I go about testing new products on the job without destroying my skin barrier in the process, which I’ve unfortunately done on several occasions over the years.

For starters, I never introduce more than one new product into my routine at a time because how else am I supposed to know what’s working and what’s not? We’ve got to “isolate the variable,” as my science teacher used to say. Also, flooding your skin with too many ingredients at once increases the likelihood of causing irritation or breakouts.

Next, barring any immediate reactions like redness, itching, bumps or excessive drying, I’ll continue to use the new product for 12 weeks before ultimately deciding whether it stays in my daily routine or gets dropped for something else.

Why 12 weeks? On average, your skin cells turn over around every 28 to 40 days (which slows down with age), so it could take a full month to start seeing any noticeable results like a reduction of dark spots or blemishes. And to truly assess whether a product has made a change in the overall tone and texture of your skin, you want to give it at least a few cycles. 12 weeks equals roughly three cycles, give or take a few days. OK, that’s enough math for this gal.

I know 12 weeks seems like a long time to wait in this day and age, but after a decade of testing more products than I can count—each one with more compelling claims than the last—I’ve realized over and over again that there are no quick fixes with skincare.

Anything worthwhile takes time. Especially if you’re looking to clear up, lighten, brighten, tighten or firm anything. These things require consistency and patience, so don’t get discouraged and prematurely throw in the towel on that pricey new serum that doesn’t seem to be doing much two days or even two weeks in.

Give your products time and you just might be surprised. At a minimum, you’ll definitely save some money and your skin from undue stress.

Jenny Jin Headshot Vertical 2023

Beauty Director

Jenny Jin is PureWow’s Beauty Director and is currently based in Los Angeles. Since beginning her journalism career at Real Simple magazine, she has become a human encyclopedia of...