The first time I stocked up on face sheet masks, I was in Seoul, South Korea. I spent an afternoon with a latte, people watching and marveling at the fashion. I also couldn’t help but notice that the average Korean woman’s skin was far superior to my washed out, travel weary face.

I needed to get in on the skincare action.

I started by filling my carry on (which is the only sized suitcase that I travel with) to the brim with sheet masks. It was easy to buy them in bulk, so filling one whole side of the suitcase with them truly didn’t seem excessive. Then after I returned home, I made sheet masks a ritual. I used them on the rare occasions I wasn’t rushing around. They were stuck on my face prior to a bath. I even used them when I was pregnant to retain some semblance of normalcy alongside my rapidly expanding belly.

Now that they have become a part of my beauty routine, it was only this year that I wondered, “What the heck are in these things?” The packages often boast “serums” which could be a whole host of ingredients. Plus, when they say “honey” is it used ironically, the way McDonalds sells chocolate-y chip cookies?

I did a little digging. Here are some things to be aware of if you are also relishing the trend of looking like a cross between Mike Myers and a sad ghost.

Sadly, there are a lot of toxic chemicals that are mixed together with the intention of giving you that “healthy glow.” Here are some of the common ones to be aware of:

Parabens: placed in products to help stop the growth of microbes, these are often in products with the intention of prolonging the shelf life. However, they also are proven endocrine disruptors and carcinogens. If you plan on making sheet masks a habit, it is best to start reading the labels the way you started doing on your cereal boxes. (1)

Formaldehyde. You probably don’t think this ingredient is a healthy one, but you also probably don’t suspect that you have willingly put it on your face. There is sufficient evidence that this ingredient causes cancer in humans. Best to stay clear. (2)

Phthalates: These chemicals allow the sheet masks to retain their moisture and also are a cost-effective way to maintain durability. The problem is that they are also endocrine disruptors and have links to infertility. Oh, and by the way, they are banned in Europe. (3)

Sulfates. Products are now declaring that they are “sulfate free” but do you even know what that means? (Me neither.) Aggressive detergents made out of sulfur salts, these are what is behind the foaming action we associate with “clean.” Sulfates have the potential to be tainted by a known carcinogen. It is also important to note that even those “sulfate free” rely on chemical compounds that are only an atom away from true sulfate. (3,4)

Of course, you could have the best of both worlds and make your own. The actual sheet masks are incredibly inexpensive in bulk and you could even DIY the mask itself, using an old cloth or shirt that you have cut up. Chamomile tea, oatmeal and yogurt or olive oil and honey are some all natural ways for you to channel the look of Mrs. Doubtfire.