Mattress types

Inner-spring

This mattress has been around the longest — and it's the one people are most familiar with. The mattress's core is made of tempered steel coils, which give it that all-familiar boing-boing. The mattress is covered in layers of upholstery for insulation and cushioning. An inner-spring queen mattress can cost roughly $200 or $300 and up to $4,000 or more.

Foam

These mattresses are either made of a solid core of foam or have several layers of different foams, including latex and visco-elastic "memory" foams, like the kind in Tempur-Pedic beds — which, like most mattresses, come in various models in a wide price range ($1,200-$6,000 for a queen). Because of the special material, the mattress conforms to and supports your body and is supposed to relieve pressure that can cause pain while lying down. You'll sink down into one of these and do not spring back up. These mattresses are heat-sensitive, so they can often be a little warmer than an inner-spring.

Air beds

These look like a standard mattress and box spring, but instead of springs or foam, their support is air. This is the type of mattress on Select Comfort's Sleep Number bed ($1,000-$4,000 for a queen), for example. This mattress allows you to fine-tune its firmness to your needs, so that you can have a firmness number of say, 35 on your side, and your partner can have a firmness of 80 on theirs. A pretty neat idea that accommodates the different preferences that a couple may have.

New trends in mattress design and construction

Single-sided mattress

You probably never flipped your mattress every few years like you were supposed to. Ever since Simmons introduced its single-sided mattress in 2000, many of the newer mattresses are made so that you don't need to flip them. (Some experts suggest that some mattresses still be rotated from head to toe.)

More layers, more comfort?

There's a big move toward increasing the amount of memory foam or latex, which provides a cushion and increases comfort. Industry experts say that: "This is certainly better than the polyester batting that we saw in years past, which has a tendency to compress and lose its loft over time, which can make for more of an indent."

Latex:  So, what if you have a latex allergy — should you be concerned about buying a bed that contains latex? No, according to manufacturers and medical professionals, who say people with latex sensitivity are allergic to a protein in the latex. Manufacturers run the latex through a process that cleanses those proteins. At least that's the process used for the three big manufacturers:  Sealy, Simmons, Serta and Spring Air.

Memory foam: These mattresses are made with a new generation of memory foam, which keeps you cooler.  Some new Tempur-Pedic models come with an "airflow system convoluted layer", basically a pad that helps you stay cooler.

Outlast: If temperature preference is crucial for you and your sleep partner, then keep the word "Outlast" at the top of your shopping list. Several mattress companies, including Serta and Select Comfort, are using Outlast technology, which adjusts the mattress to your body temperature. If you testthe Sleep Number 9000 bed, you will find that one side is warm, while the other side is cool for your partner.

Cashmere, silk, merino wool: You'll see these "luxury fabric" watchwords on more and more mattresses. Do they mean much? Not really, according to industry insiders. It's a minuscule amount that's only used in the ticking (the outermost layer) which may not impact anything. It's more of a marketing tool than anything.

Major Bed Brands: Prices Differences: Duxiana, Select Comfort, Tempur-Pedic

Many of the estimated 70 million Americans who complain of sleeplessness have turned their backs on conventional innerspring beds and bought alternatives such as Duxiana (springs galore, in layers), Select Comfort (air-filled, with adjustable firmness for each partner), and Tempur-Pedic (polyurethane "memory foam").