Beauty sleep: When you can hardly fall asleep most nights, it sounds more like a fairytale than an attainable reality. Overnight beauty products claim to work double-duty while you sleep to help fake those eight hours, while silk pillowcases are touted for having serious beauty benefits, like reducing wrinkles, split ends, and frizz. But can silky bedding really be the path to smoother skin and better hair?

In short, yes — silk pillowcases really do make a difference. After we tested the best silk pillowcases in the Good Housekeeping Institute Textile Lab, many of our editors began sleeping on the luxurious bedding and now swear by silk pillowcases, with one saying, "I realized my cheap pillowcase was the real culprit behind my bad hair days."

That said, silk pillowcases aren't a cure-all for all of your beauty woes: We spoke with Dr. Neal Schultz, New York City-based dermatologist and author of It's Not Just About Wrinkles, to get the scoop on what beauty benefits you can actually expect from silk pillowcases, and what's just fiction.

Silk pillows provide a host of benefits that will leave you feeling refreshed every morning. We have the details on how a silk pillowcase can send you to the stars.

What are the silk benefits of silk pillowcases? 

It keeps skin cooler: While synthetic fibers trap heat, natural materials like silk are considered more breathable. “Silk is thought to keep skin cooler and reduce excessive sweating,” says Dr. Emma Wedgeworth, consultant dermatologist and British Skin Foundation spokesperson. When our skin is kept at a colder temperature, it’s less prone to redness and inflammation. That’s exactly why treatments like cryotherapy are known for de-puffing and reducing redness.

It keeps skincare on our face: Whether you have a hefty or lightweight routine, no one wants their skincare to slip or rub off the skin during the night. That means, the serums and moisturizers we apply pre-bedtime have a better chance of staying where they belong: on our faces. Silk is actually known for being less absorbent compared to synthetically-derived materials. According to silk brand, Slip, this material causes 43% less friction than cotton pillowcases with a thread count between 220-360. So, the moisture we apply to our face at night won’t rub off nearly as much.

It reduces skin creasing: We’ve all experienced the rude awakening of getting out of bed to discover a pillow crease mark has indented itself into our cheek. Silk, with its particularly smooth fibers, doesn’t tug or create friction, nor does it impress its texture onto the skin. In short, it’s a much more gentle fabric which makes it perfect for caring for the fragile skin on the face.

It’s hypo-allergenic: Our faces are on pillowcases for a huge chunk of the day — and if you have acne-prone or sensitive skin, you’ll know the worry that can come with sleeping on your face. Silk is antibacterial and hypoallergenic, so there’s less of a chance your pillowcase will harbor harmful germs.

What are the hair benefits of silk pillowcases?

It retains moisture: “Silk pillowcases don’t steal your skin and your hair’s moisture while you sleep,” explains hair loss consultant, Simone Thomas. This is all thanks to its absorbency rate. According to the Hellenic Silk Company, silk absorbs 11% of moisture (from skin and hair) in normal conditions. Other synthetic fabrics usually have an absorption rate of 30%, meaning silk won’t zap as much moisture from your hair.

It reduces bed head: “The material is a lot less rough on the hair than regular pillowcases, “ says Thomas. The main reason for this? Silk is an anti-static material. As a result, hair follicles aren’t as roughed up as we move around in our sleep. In testing conducted by Slip, the brand found that its users experience 43% less friction than cotton pillowcases.

It reduces breakage and thinning: “Our hair, skin and whole body is constantly moving and being aggravated when we sleep,” says Thomas. “This amount of moving can cause the hair to break, create thinner hair, frizz, bed head and split ends.” The natural, smooth texture of silk prevents friction between the hair and the pillowcase.

What to look for in a silk pillowcase?

Of course, like every other product that promises better sleep, not all silk pillowcases provide the same benefits. Here are a few things to look for when choosing a silk pillowcase:

• A high-quality silk pillowcase should be made of pure 100% mulberry silk, like those available at Casper. In fact, if you’re looking for an even deeper slumber, check out our Silk Pillowcase + Sleep Mask Set, which comes with a 100% mulberry silk sleep mask.  
• Beware of silks that include blends of other fabrics—particularly silk that includes synthetic materials, such as rayon and polyester. Compared to pure silk, these combinations are unlikely to offer the same level of benefits.
• Choose a silk pillowcase that comes in the right pillow size for your bed so it doesn’t slip off while you sleep. After purchasing a silk pillowcase, the last thing you want is to end up sleeping on a bare pillow.
• Depending on your taste and style, you’ll want to find a silk pillowcase available in multiple colors to coordinate it with the rest of your bedding. At Casper, our silk pillowcases come in several luxurious looks.

And of course, the fabric of your silk pillowcase should feel lustrous, opulent, and friction-free. After all, the goal is to give you the smoothest, most tranquil night’s rest on earth.

Can you wash silk pillowcases?

One of the first questions often raised by those considering a silk pillowcase concerns keeping it clean. People imagine that it is easily damaged and therefore must be hand-washed, but this simply isn’t the case. It can be machine washed at 30 degrees – and usually dries far more quickly than its cotton counterpart, too.

It is also surprisingly robust. It is strong as well as super soft, and even repels night-time nasties, such as bed mites or other creepy-crawlies. If you don’t want to share your bed with unwanted guests, a silk pillowcase is a must.

Top Questions About Silk Pillowcases

1. Can silk pillowcases prevent wrinkles?

Believe it or not, they can! A "smooth surface with very little friction" means less tugging on the skin than with a traditional cotton pillowcase, says Schultz. “We get 'crush wrinkles' from sleeping on our side/face, so we may get less of those when sleeping on silk.” Studies show that friction from tossing and turning causes creases in the skin, but a silky smooth surface can reduce that effect in the long run.

2. Do silk pillowcases prevent frizzy hair?

Yes! Thanks to silk's super smooth texture, hair glides over it without any friction which means you'll be less likely to wake up with frizzy hair, tangles, or bedhead, whereas cotton can snag hair and muss it up into a nest of tangles overnight. Sleeping on silk is a secret that women with textured and curly hair have been using for years to keep styles like braids and blowouts preserved for longer without adding frizz.

3. Do silk pillowcases keep skin hydrated?

Thanks to that super-smooth texture, this is actually true. Silk's smoothness “means it’s less apt to absorb moisture from the skin,” says Schultz, keeping skin nice and hydrated without zapping it of valuable moisture. That makes silk pillowcases great for anyone with dry skin (or for use in dry winter months).

4. Do silk pillowcases keep hair healthy?

In some ways, yes: They help keep hair hydrated, and Schultz says that silk can help with brittle hair. Cotton is more porous than silk, so traditional pillowcases absorb moisture from your hair, while silk leaves that hydration right where it belongs: in your hair. That means if you suffer from dry strands or a flaky scalp, a silk pillowcase will be a godsend.

5. Can silk pillowcases regulate temperature?

Silk may not be the most cooling bedding option, but it certainly does regulate temperature. According to Lexie Sachs, Associate Director of the Good Housekeeping Institute Textiles Lab, silk fibers are inherently temperature-regulating. Unlike cotton, which absorbs moisture, silk wicks moisture away to keep you dry and cool all night long.

6. Do silk pillowcases prevent acne?

Not necessarily. It’s true that silk doesn’t absorb as much moisture as cotton, but you shouldn’t expect it to clear up acne or prevent breakouts. Instead, if you suffer from breakouts or adult acne, you’re better off adopting an acne-clearing skincare regimen (and stop touching your face!).

7. Are silk pillowcases naturally hypoallergenic?

Unless your allergies are directly related to your bedding, don’t bet on it. The claims that silk is naturally hypoallergenic are “not relevant to most people,” says Schultz. If you do suffer from allergies, try adding a mattress protector to your bed to block allergens and environmental irritants, and be sure to regularly wash your bedding.

8. Do the amino acids in silk pillowcases improve your skin?

Nope. Schultz explains that while silk contains amino acids and natural protein (and that amino acids are great for skincare), they can’t be transferred to the skin for any measurable benefit.

9. Can silk pillowcases prevent split ends?

The slippery smooth texture of silk will prevent tangles and frizz, but it can’t prevent hair breakage and damage altogether. Instead, try using a deep conditioner and getting regular trims to prevent split ends.

10. Are silk pillowcases anti-aging?

Sort of. Silk pillowcases can decrease wrinkles and improve the appearance of skin’s hydration, which can make you look more youthful. But if anti-aging is your goal, remember that fine lines and “wrinkles only account for 5 percent of your face.” That means you'll also need to combat signs of dull skin and uneven skin tone with the right products and treatments, advises Schultz.