It's that time of year when you begin thinking about bringing your feet out of hibernation. But trudging around in winter boots for months has taken its toll: You've built up thick calluses and layers of dead skin. You could spend hours pummeling them with a pumice stone—or you could try Baby Foot, a product that's created lots of buzz with its claims to rid your feet of the grossest, toughest calluses and leave them as soft as, well, you know what. But what the heck is in this product, anyway? Does it really work? And is it safe? Here's what we found out. (Want to pick up some healthier habits? Sign up to get FREE healthy living tips and more delivered straight to your inbox!)
 
What it is: Baby Foot, which has been selling in Japan for over a decade and became available in the United States in 2012, is essentially two plastic booties lined with a gel made with alpha hydroxy acids (AHAs), or fruit acids, including lactic, glycolic, and citric acids. These acids, along with 17 types of natural extracts such as lemon, grapefruit, sage, and ivy, penetrate into the layers of dead skin cells and break down the desmosomes, or cell structures, that hold skin together. (Are you guilty of one of these 4 beauty habits that are making you age faster?)

 "It basically acts as a very strong exfoliant," explained Dr. Debra Jaliman, a dermatologist at the Mount Sinai School of Medicine in New York City. The extracts also have moisturizing effects, which helps make your soles baby soft. 
 
How it works: You place the two plastic gel-filled booties on your feet (the company recommends soaking feet in warm water first, to soften them and increase absorption); sit with the booties on for an hour, preferably with socks over them (heat enhances the results); then rinse the gel away. Peeling should start 3 to 7 days later. Since the peeling process is not the least bit subtle, Baby Foot is not for the faint of heart: "Giant swaths of skin separated from my feet and came off with just the lightest tug," writes one online reviewer. "Whole sheets of skin came off in a go," writes another. Within 2 weeks, after you've shed like a snake, voilà, baby soft skin.

A photo posted by BabyFootUSA (@babyfootusa) on

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What the expert says: "I have patients who swear by Baby Foot—it does work," Jaliman admitted. "It's an appealing option, especially for women who live in a city where they have to walk a lot. It's easy for feet to get hard and callused quickly," she adds, "and if you don't have time to keep up with them weekly or go for regular pedicures, you run into problems."

But there are caveats: Jaliman doesn't recommend using the product if you have any kind of open sore on your foot, even a small cut. "The acid will seep into the crack, causing excruciating pain, and also increase your risk of developing a skin infection," she warns. She also doesn't recommend it if you've got sensitive skin or eczema because the acid can irritate the skin, causing swelling and inflammation. Also avoid the product completely if you're diabetic, since you're more prone to foot infections and may have nerve damage that could keep you from feeling warning sensations, such as burning, in your feet, Jaliman added. (Yikes, is that just a mole—or something worse? Check out these pictures of what to look for.)

And while most users rave about this product, there are horror stories: "My feet started to not only flake and peel but also crack… They were bleeding on the floor when I walked and when I covered them it was worse," wrote one reviewer. "I could hardly walk and it was very painful. After removing a bandage, I could smell a yeasty smell and got on the computer. I had a very bad fungal infection." A few other testers report having to see their doctor or even go to the ER to treat blisters and burns.
 
Other options: If you're willing to go only so far for smooth, silky soles, Jaliman suggested products that she says are just as effective but less risky: the Diamancel Foot Buffer, a buffer with a geometric diamond pattern on its surface to remove dead skin, or the Emjoi Micro-Pedi Callus Remover, a battery-operated device that buffs away calluses in seconds. If you like doing your footwork in the shower, try Amopé Pedi Perfect Wet & Dry Foot File, a waterproof electronic roller that sloughs off dead skin in seconds and is cordless and rechargeable.

This article originally appeared on Prevention.com.