Why you should stick with a skin-care routine for at least 28 days

We live our lives on a 24-hour cycle. It’s some iteration of wake up, work out, go to work, eat, shower, and then repeat—with a glass of wine or a green juice thrown in every once in a while for good measure. But while our brains and bodies can rest, recover, and revive over the course of that short stint, our skin needs a whole lot more time to undergo the same process. Like 28 of those 24 hour-cycles, to be precise.

An adult’s skin regenerates itself over the course of four weeks (sometimes longer), a process that involves a new skin cells forming beneath the surface to replace a matured one, which will eventually slough off. “Think about planting a tulip bulb, and you have to wait until it grows and blooms—you plant them and then over the month they come up and bloom and it smells so good, but you can’t really rush the process,” says New York City dermatologist Ellen Marmur, MD. “The way the skin is made, it has a basement membrane that is like a layer, but it’s where everything comes from, so all the cells called keratinocytes—the skin cells—all come from this basement membrane, and then they grow. As they’re growing, they’re changing and maturing and developing. So they go from babies to toddlers to adolescents to adults, and then at the very top of the skin, they’re as mature and strong as they can possibly be.”

She explains that people are always trying to make this process move more quickly by scrubbing off the top layer of their skin, which winds up doing more harm than good. “You really shouldn’t be doing that in your everyday routine because it’s stressful on the skin and it provides a lot of inflammation and free radicals and stuff like that,” she says. “So there’s a vicious cycle; I think in the marketing of the skin-care world right now, sort of overworking the skin can backfire.”

And she’s right: These days, we all expect to scrub our faces and slap on a product before bed and wake up looking ageless and radiant. But even if that were possible, it may not necessarily be the best idea for the longterm. And what’s more, it actually takes 28 days of using a product and really sticking with it to know if something is working for you or not. Keep scrolling to find out why.

What does this cycle actually look like?

The 28-day skin cycle starts from within, meaning that you need to let things happen beneath the surface. “You don’t really want to speed up the cycle,” says Dr. Marmur. “What you can do to have the illusion of speeding up the cycle is use hydrating serums—that include ingredients such as hyaluronic acids, aloe, and anti-inflammatories like peptides. Those types of things can give you the illusion of radiant skin much faster.”

So really, all you can do is wait. “You might want your pores to be tighter, you might want wrinkles to be softened, you might just want to glow more; all of that is about better skin surface, which is having a more mature skin surface, and possibly even more hydration in the skin,” says Dr. Marmur. “Mature skin,” as she explains it, is a reflection of allowing your skin enough time to grow, repair, and balance itself so that it can ultimately look its best. 

How do your hormones play in?

We all know that skin and hormones are directly linked (see: the pimple that pops up on my chin every month before my period). After all, there’s a reason why our cheeks plump up and we get a nice, glow-y flush when we’re ovulating. So while the 28-day cycle that your skin goes through is technically an entirely different one than your 28-day hormonal cycle, it’s important to acknowledge that they don’t occur in isolation of one another—they may not happen on the same timeline, but they are still happening simultaneously. “Your skin has different needs depending on the various levels of hormones during your menstrual cycle,” says NYC dermatologist Joshua Zeichner, MD, noting that while “28 days” is a solid barometer, some women experience both longer and shorter cycles in terms of menstruation and their skin.

“When we’re learning about the cell turnover cycle, we’re not connecting it at all to the ovulation cycle—men also have a 28-day cycle on their skin turnover,” says Dr. Marmur, before adding the caveat that hormones “totally affect the skin.” “We all have that progesterone and break out, and testosterone definitely affects the skin,” she explains, so while there’s no science (yet) to prove any sort of link, she wouldn’t be surprised it if existed.

What can we learn from this?

In the age of instant gratification, it’s easy to expect our skin to operate on the same cycle that the rest of our lives do (which, for what its worth, happens to be the same as a man’s 24 hour testosterone cycle. Just saying.). Because, of course, we all want to test out a product for the first time and wake up in the morning to find glowing, healthy skin. But we could stand to take a hint from our bodies, and learn to be patient while our body does its business.

“Loyalty to products is a good thing,” says Dr Marmur. “With a lot of trends, the marketing is so exciting that you keep going from product to product to product, and that can be bad, so just try to remind yourself to be patient and loyal. And even after that 28 days, you’re going to see more and more benefit.” Your skin needs time to do its thing, so instead of trying to rush through the process—the way we often rush through everything else in our lives these days—the best thing you can do, really, is sit back, relax, and wait a beat to see how things are going.

Can’t tell if your products are working or not? Peep this guide to figure it out. Plus, here are all of the drugstore skin-care products dermatologists can’t stop raving about.