Sleep matters—so much so that six in 10 Americans report craving sleep over sex. The key to rest good enough to forgo sex? It just might be in the mattress.

Nine in 10 respondents in a sleep survey cited their mattress as an important factor in getting that coveted good night’s rest. Americans love their beds so much, in fact, that they're willing to shell out thousands of dollars for a single mattress. But the word is still out on whether this expense is really justified, since mattresses can affect our sleep in both positive and negative ways. Make sense of the bedding madness with this primer on choosing the right mattress for you.

Mattress Matters—The Need-to-Know

The first “mattresses” (read: piles of leaves, grass, or straw covered in animal skins) were invented by cave men and women. Thousands of years later, the Egyptian pharaohs discovered the luxury of raising the bedding off the ground (though "common folk" continued to sleep on piles of palm bows). Today, many Americans enjoy mattress-induced rest.

Six in 10 Americans crave sleep over sex

But mattresses don't always help people obtain a good night's sleep. Low-quality, uncomfortable mattresses have been linked to sleep discomfort and pain, and chronic pain can prevent quality sleep Effect of prescribed sleep surfaces on back pain and sleep quality in patients diagnosed with low back and shoulder pain. Jacobson, BH, Boolani, A., Dunklee, G., et al. Oklahoma State University, Oklahoma. Applied Ergonomics, 2010 Dec;42(1):91-7 Sleep disturbance in patients with chronic low back pain. Marin, R., Cyhan, T., Miklos, W.Physical Medicine & Rehabilitation Service, Department of Orthopedics and Rehabilitation, Walter Reed Army Medical Center, Washington, D.C. American Journal of Physical Medicine and Rehabilitation, 2006 May;85(5):430-5 . Those who struggle with sleep deprivation may suffer from a sour mood, slower metabolism, and impaired immune function Effects of sleep deprivation on performance: a meta-analysis. Pilcher, JJ and Huffcutt, Al. Department of Psychology, Bradley University, Illinois. Sleep, 1996 May;19(4):318-26 REM sleep deprivation induces changes in coping responses that are not reversed by amphetamine. Martinez-Gonzalez, D., Obermeyer, W., Fahy, JL, et al. Department of Psychiatry, University of Wisconsin-Madison. Sleep, 2004 Jun 15;27(4):609-17 Role of sleep and sleep loss in hormonal release and metabolism. Leproult, R. and Van Cauter, E. Department of Medicine, University of Chicago, Illinois. Endocrine Development, 2010;17:11-21 Impact of sleep and sleep loss on neuroendocrine and metabolic function. Van Cauter, E., Holmback, U., Knutson, K., et al. Department of Medicine, University of Chicago, Illinois. Hormone Research, 2007;67 Suppl 1:2-9 Sleep, immunity, and circadian clocks: a mechanistic model. Bollinger, T., Bollinger, A., Oster, H., et al. Institute of Medical Microbiology and Hygiene, University of Luebeck, Germany. Gerontology, 2010;56(6):574-80 .

Fortunately it’s not all bad news. While mattresses can hinder sleep quality, they can also improve it. Better “bedding systems” (a fancy way of saying “things you sleep on”) have been linked to decreased pain and discomfort, especially in women Effect of prescribed sleep surfaces on back pain and sleep quality in patients diagnosed with low back and shoulder pain. Jacobson, BH, Boolani, A., Dunklee, G. Oklahoma State University, Oklahoma. Applied Ergonomics, 2010 Dec;42(1):91-7 Effectiveness of a selected bedding system on quality of sleep, low back pain, shoulder pain, and spine stiffness. Jacobson, BH, Gemmell, HA, Hayes, BM, et al. School of Applied Health and Educational Psychology, Health and Human Performance, Oklahoma State University, Oklahoma. Journal of Manipulative and Physiological Therapeutics, 2002 Feb;25(2):88-92 . Quality sleep on a good mattress may also help decrease stress Changes in back pain, sleep quality, and perceived stress after introduction of new bedding systems. Jacobson, B., Boolani, A., Smith, D. Journal of Chiropractic Medicine, 2009 March;8(1):1-8 .

The long and short of it? A bad mattress can contribute to poor sleep quality, while a good mattress can improve it. Given that the average person spends about one third of her or his life sleeping, it's worth investing the time (and money) to find the right mattress for you.

Better Bedding—Your Action Plan

How to Pick the Perfect Mattress, According to Science

When it comes to purchasing the perfect mattress, it turns out there are a lot of mixed messages out there. Some research suggests foam mattresses create backaches; others say foam helps pain. Some studies advocate for regular cotton mattresses while others say coils create backaches and that airbeds are the way to go The foam mattress-back syndrome. Koul, PA, Bhat, MH, Lone, AA, et al. Department of Internal Medicine, Sher-I-Kashmir Institute of Medical Sciences, India. The Journal of the Association of the Physicians of India, 2000 Sep;48(9):901-2 Short-term outcomes of chronic back pain patients on an airbed vs innerspring mattresses. Monsein, M., Corbin, TP, Culliton, PD, et al. Sister Kenny Institute Chronic Pain Rehabilitation Program, Minnesota. Medscape General Medicine, 2000 Sep 11;2(3):E36 . There’s even disagreement over whether a firm mattress really is better for lower back pain Effect of firmness of mattress on chronic non-specific low-back pain: randomized, double-blind, controlled, multicenter trial. Kovacs, FM, Abraira, V., Pena, A., et al. Scientific Department, Kovacs Foundation, Spain. Lancet, 2003 Nov 15;362(9396):1599-604 Better backs by better beds? Bergholdt, K., Fabricius, RN, Bendix, T. Back Research Center, Part of Clinical Locomotion Science, Backcenter Funen, Denmark. Spine, 2008 Apr 1;33(7):703-8 .

The reason for all this controversy is that sleep quality and comfort are so darn subjective The influence of bed firmness on sleep quality. Bader, GG and Engdal, S. Department of Clinical Neurosciences, Sahlgren’s University Hospital, University of Gothenburg, Sweden. Applied Ergonomics, 2000 Oct;31(5):487-97 . In fact, when buying a mattress, the most important consideration is probably personal comfort. (That also means that if something besides a mattress proves more comfortable to sleep on, we should go for it Instinctive sleeping and resting postures: an anthropological and zoological approach to treatment of low back and joint pain. Tetley, M. British Medical Journal, 2000 December 23; 321(7276): 1616–1618 ).

If you find yourself in the market for a new mattress, follow these guidelines for a better shot at getting that elusive good night’s sleep.

  • Replace a mattress approximately every eight years. Keep it longer than that and the materials may start to degrade, which might make the mattress less comfortable to sleep on. If you’re waking up in pain every day, sleeping poorly, or feeling disgruntled all the time, consider upgrading sooner Grouped comparisons of sleep quality for new and personal bedding systems. Jacobson, BH, Wallace, TJ, Smith, DB, et al. School of Applied Health and Educational Psychology, Applied Musculoskeletal and Human Physiology Research Laboratory, Oklahoma State University, Oklahoma. Applied Ergonomics, 2008 Mar;39(2):247-54 .
  • Replace the box spring along with the mattress. Over time, the compression of the springs (which results from having a mattress and human bodies on top of it) will start to change the structure of the spring box. To retain proper structure, replace it every eight years or so—or just ditch the box spring altogether.
  • Make comfort your goal. Purchasing a mattress is all about finding the best one for you. Some people like a firm mattress; some like a soft one; others, like Goldilocks, prefer somewhere in between. The experts we spoke to said it basically comes down to personal preference. If you're comfortable, you have a better chance of sleeping well.
  • Try before you buy. Test “sleep” on a mattress for at least 20 minutes in a normal sleep position before making a decision.
  • Look for a mattress that fits your body. Chiropractors advocate finding a mattress that’s designed to conform to the spine’s natural curve and distribute pressure evenly across the body. This can be tricky, because the surface curve on the mattress doesn’t necessarily represent the way your spine will curve while sleeping on it The relationship between surface contour and vertebral body measures of upper spine curvature. Refshauge, KM, Goodsell, M., Lee, M. School of Physiotherapy, Faculty of Health Sciences, University of Sydney, Australia. Spine, 1994 Oct 1;19(19):2180-5 . Everyone’s pressure points are different, so the best way to figure out if a mattress correctly supports the body is to bring a friend along to the store. Lie on the mattress in your normal sleeping position and ask your friend to observe whether your spine remains fairly neutral. If your spine is obviously sagging or curved exaggeratedly in any given direction, then keep searching for a mattress that helps maintain neutral spine alignment.
  • Avoid the sag. While researchers are challenging the idea that a firm mattress is essential for anyone with back pain, most experts still agree a saggy mattress isn’t the way to go Better backs by better beds? Bergholdt, K., Fabricius, RN, Bendix, T. Back Research Center, Part of Clinical Locomotion Science, Backcenter Funen, Denmark. Spine, 2008 Apr 1;33(7):703-8 . To determine if a mattress has too much sag, perform the same spine alignment observation outlined above.
  • Don’t buy vintage. Not only is the mattress likely to have lost its proper structure, but this ruIe’s especially important if you’re worried about your bed catching on fire. Only mattresses made after July 2007 must meet regulations for fire resistance.
  • Ignore brand names. Virtually all mattress coils are made by the same manufacturer. Likewise, don’t be duped by dollar signs: A higher price doesn’t necessarily mean better quality.
  • Bigger doesn’t necessarily mean better. Thickness is often just a visual ploy designed to get people to think they’re buying a comfier mattress. Listen to your body and find the bed that feels the most comfortable (not the one that just looks that way).
  • Beware of allergens. If you have allergies (particularly to dust mites, mold, and certain bacteria), read the mattress’ label to make sure that the materials don’t contain any sneaky allergens—or, better yet, look for a hypoallergenic mattress (natural latex and wool are both decent options) or a mattress cover. Worried about allergies but don’t want to pay for an expensive mattress cover? Daily vacuuming might help Daily vacuuming of mattresses significantly reduces house dust mite allergens, bacterial endotoxin, and fungal β-glucan. Wu, FF, Wu, MW, Pierse, N., et al. International Emergency Medical Development Center, Taiwan. Journal of Asthma, 2012 Mar;49(2):139-43 .
  • Do not disturbyour partner. If you share a bed, look for a mattress that allows two people to adjust the firmness on their respective sides. That way, neither one of you will have to sacrifice comfort or spine alignment.
  • Give peace a chance. Even if you loved your new mattress in the store, you might not sleep better on it the first night you bring it home. It can take a couple of days to adjust to a new sleeping surface The influence of bed firmness on sleep quality. Bader, GG and Engdal, S. Department of Clinical Neurosciences, Sahlgren’s University Hospital, University of Gothenburg, Sweden. Applied Ergonomics, 2000 Oct;31(5):487-97 . If the first night on a new mattress doesn’t transform your sleep quality, give it a few more nights before giving in to buyer’s remorse.
  • Look for a return policy. This way, you won’t be stuck with an expensive mattress that doesn’t provide the sleep of your dreams.

Thanks to Joyce Walsleben, David M. Rapoport, and Nicole Lehman for their help with this article.

Withings Logo-In-Post This article is part of our Connected Wellness series with Withings, a consumer electronics company dedicated to creating smart products to help you make healthy and balanced choices. We take our partnerships seriously, which is why we’ll never collaborate with a brand unless we profoundly believe in their mission. We think Withings fits that bill—we trust them to make a difference and they trust us to write great articles that (like everything on our site) are science-backed, informative, and original.

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