Mattress 101 – What you really need to know before making your next purchase

In Mattress 101

Bob Rasmussen
Founder of IntelliBED

Choosing a new mattress has been rated as one of the worst consumer buying experiences ever, and with good reason…
What do I look for, they all sound so similar?
Can I really choose the best mattress by only lying on it in a store for a few minutes?
Do I really trust what the salesperson is saying or is he pushing the mattress that pays him the highest manufacturer commission?

The Challenge of Choosing the Ideal Sleep Surface:

Before you can determine which is the best mattress, you must understand what the body requires when lying down. Structurally, our bodies need two things – good back support so that our skeletal structure is aligned in its least stressful state; and pressure relief on our sensitive hips and shoulders so we don’t toss and turn all night.

What is good back support? We all understand the importance of sitting and standing straight. We must also sleep straight! But here is the problem. Our lower torso is the heaviest part of our body and naturally will sink deeper into the mattress. Your mattress must prevent this from happening. The mattress must push the hips up so that our spine does not sag into a hammock shape, and keep in mind most foam mattresses can sag up to 40% in the first few years. Poor support from your mattress is a leading cause of back pain, and if you are waking up with back pain, it indicates you are not being supported properly.

What is pressure relief? Most mattresses rely on foam to cushion the body, however, when you compress foam, (ie where your hips and shoulders sink deepest into the surface) the bottom of the well creates a hard surface. So as your hips and shoulders protrude into the surface of the mattress further than our side, back and legs, this in turn creates uncomfortable pressure points. Excessive pressure on the skin cuts off blood flow to the tissue, which is the cause of decubitus ulcers (bed sores). The brain knows this and will arouse us from the deeper stages of sleep, so we can turn over. It takes about 90-minutes to complete a sleep cycle, and it is at the bottom of these sleep cycles that the most beneficial stages 3-4 of sleep occur. Tossing and turning fragments our sleep and robs us of stage 3-4 sleep (every time we turn we go back to stage 1, thus shortening/interrupting our stage 3-4 deep healing stage). Lack of stage 3-4 sleep is linked to such disease states as diabetes, heart disease, obesity; not to mention the dangerous and unproductive condition of daytime drowsiness.

The dilemma: How do you forcefully push on the hips so they don’t sag into the mattress, but then relieve the pressure point caused by doing so? Balancing the NEED for both back support and pressure relief is THE challenge of the mattress industry! But also consider that as we age, our need for support and pressure relief increases but the performance of mattresses diminishes with use, so another important consideration that must be evaluated is Durability, which is defined as the ability to maintain consistent support and pressure relief for the life of the mattress.

Other less critical sleeping needs include Sleep temperature: The ideal sleep surface will not sleep hot or cold; and Motion Transfer: For some, every movement of their sleep partner disturbs their sleep and wakes them up.

Toxicity:  Although not a performance issue, the materials in the best mattresses must be safe and not off-gas harmful substances. This has become an issue as manufacturers experiment with compounds to change the characteristics of foam (for example, changing polyurethane foam to memory foam) and the requirement all manufacturers have to meet certain flammability standards forced upon the industry by our Federal Government.

The four PILLARS of Healthy Sleep:

To summarize the discussion, we can boil our most important sleeping needs into what we call “The four pillars of healthy sleep”. They are:

  • Support
  • Comfort
  • Safety
  • Durability

Adjustable Air, Latex, Memory Foam, Innerspring – so many choices – which is best at addressing the Four Pillars?

Before discussing various technologies, let’s take a minute and talk about foam since every mattress manufacturer relies on foam to cushion the human body.   There are many different types of foam including memory foam (polyurethane foam with an additive to slow the rebound), gelled memory foam (memory foam with chunks of gel imbedded into the foam for cooling), latex foam and standard polyurethane foam. Regardless of the type, all foam has two inherent problems that prevent them from being ideal:

  1. Foam is compressible, meaning that the further you push into foam, the harder it pushes back. Our hips and shoulders stick out further, compressing the foam further and this is the reason we experience uncomfortable pressure points.
  2. Foam quickly softens and breaks down. Nearly all of us have experience with body impressions in the top of our mattress. This is caused by the foam breaking down. Some foam is better at resisting breakdown then other, but even the best foams will soften 16% over the first two years of use, and the most common foams used in mattress softens 25-40%. But it is the way they soften that causes the real problem. Because our heavier lower torso is always in the middle of the bed, the mattress breaks down more in the middle of the mattress than anywhere else, causing our hips to sag further and further into the mattress with use.

Innerspring and Pillow-Top mattresses:   There are two different types of innersprings – laced and pocket coil. Laced or support coil innersprings have all the springs tied together, so that the springs work together to prevent your protruding hips from sagging into the mattress. Of all the materials ever developed for mattresses, support coil innersprings provide the best short and long term back support (tempered-steel springs do not break down)! Pocket-coil innersprings are not laced together, but the springs work independent of each other. Laced innerspring transfer motion, while pocket-coil innersprings don’t; but pocket coils don’t provide quite as good back support.

Innersprings are uncomfortable to sleep on and to solve this problem, manufacturers like Serta, Sealy and Sterns & Foster pile different combinations of foam on top of the springs.   Almost all innerspring units are 6” tall, so if you buy a 12” thick innerspring mattress, six inches of that mattress is foam. As the foam breaks down, you lose both comfort (the foam can’t cushion you from the firm springs below), and support (your hips sag further and further into the bed). This is the reason traditional innerspring mattress are not ideal.


Adjustable Air Beds (Sleep Number): In these beds, the innerspring is replaced by an air chamber. The advantage is that the two sleeping partners can adjust the firmness of the bed independently by either increasing or decreasing the amount of air in the chamber (through a compressor controlled by a remote control). The higher the sleep number, the firmer the bed will be. While this adjustability is a great idea, they are not ideal for two reasons:

  1. The lower the sleep number, the poorer the support will be. Think about it. The hips are heavier than any part of the body, so gravity will pull your hips further into a hammock shape compromising your support.
  2. They rely on foam to cushion your body. The air chambers in these beds are about 6” thick, so just like innerspring beds, if you have a 12” thick Sleep Number, you are sleeping on six inches of foam, and you already know how foam breaks down with use.

Memory-foam (TempurPedic and I-Comfort by Serta being the most popular). In these beds, the innerspring is replaced by regular polyurethane foam. Generally, the bottom 1/2 to 2/3 of the mattress is this polyurethane foam and the top 1/3 to1/2 is memory foam. The main advantage of these mattresses is that they don’t transfer any motion, but their disadvantages are significant. They sleep hot and they give you the feeling of being trapped in the cavity they create. I have personally pressure mapped hundreds of different shaped people on even the most expensive memory foam ($9,000 in queen size), and they don’t relieve pressure any better than any other foam mattress I have tested. Plus we have already learned the disadvantage of foam breaking down and how that compromises your long-term support.

Latex mattresses: These mattresses generally have the same build-up as the memory-foam beds with a polyurethane foam core and latex foam on top, and their drawbacks are the same as the memory foam beds. They soften too quickly compromising your support.

It is worth noting here that early on in IntelliBED’s history; we built a bed that is similar to these memory-foam and latex mattresses with a polyurethane foam core. To date, it is the only model we have ever built that we have had warranty issues with. At first people loved it, but after just two years, many users developed back pain. Testing showed it was the foam softening and breaking down causing the misalignment we have been talking about. We don’t build that bed anymore.

IntelliBED IS the ideal Sleep Surface!

While working for the earlier mentioned R&D Company, we set out to invent a replacement material for foam in mattresses to create the best mattress. Introducing IntelliGel advanced cushioning material. Intell-Gel has several distinct advantages over foam, and it is what makes IntelliBED the ideal sleep surface:

  1. Intelli-Gel is the most pressure relieving material ever created! The co-polymer gel material is formed into a gel comfort-grid that enhances the cushioning ability of the material. Instead of just compressing like foam, the gel grid collapses under the hips and shoulders allowing just those areas to sink deeply into the mattress with no pressure points. As the hips and shoulders sink in, support is transferred to the broader areas of the body – the back, side and legs, equalizing the pressure across the body and eliminating uncomfortable pressure points. Pressure map testing shows IntelliBED mattresses featuring Intelli-Gel to be up to 80% more pressure relieving than memory foam, latex or polyurethane foam!
  2. Intelli-Gel is almost indestructible. In durability testing, IntelliBED mattresses soften less than 5% over the life of the mattress. I have been sleeping on my own IntelliBED, one of the first ones ever made for well going on fifteen years and it is not showing any signs of breaking down. More important, I am extremely active and my back is very sensitive to misalignments, and I have absolutely no back pain! It is the reason we are very comfortable with our industry leading 30-year limited warranty.
  3. Intelli-Gel is completely non-toxic. I have measured the toxicity of our production line where we produce Intelli-Gel using a hand-held toxicity meter. The toxicity level there is actually less than the readings I got using the same device in my office. It has been thoroughly tested using standard cytotoxicity and hemolysis tests and found to be among the safest materials used in mattresses. The raw material has been approved to be used in baby bottle nipples!
  4. Intelli-Gel sleeps temperature neutral – it won’t trap body heat against your body, nor will it soak the heat out of your body.

IntelliBED solves the support vs. pressure relief dilemma!

  • All IntelliBED mattresses use a tempered-steel innerspring for maximum back support (with the exception of the Gel+ model).
  • All IntelliBED mattresses use Intelli-Gel as their main cushioning material for maximum pressure relief. They are so comfortable to sleep on!

IntelliBED mattresses are safe

  • Steel springs don’t offgas. Intelli-Gel is non-toxic and the small amount of foam we use is all CertiPur US certified to be free from the flame retardants and other harmful chemicals traditionally found in foam. And we don’t use spray-on chemicals to make our beds fire retardant. Instead we use a silica mesh barrier that does not off-gas!

IntelliBED mattresses are durable. They maintain consistent support and pressure relief for years!

  • Because these beds don’t break down like those beds that rely on foam for cushioning, you can rest assured that you will have years of deep, restful sleep.