The Qualities, Advantages, and Disadvantages of Memory Foam

Viscoelastic foam or "memory foam" is a very different material and perhaps partly because it has such unusual qualities compared to the many other materials used in mattresses, there is also a lot of misinformation "disguised as fact" about it. It is also subject to many different "formulas" in its manufacturing by different companies which change its qualities ... for better or for worse ... and this too becomes the subject of lots of the hype and misinformation you will hear in the world of marketing and selling mattresses.

What are the basic differences in materials used in a mattress?

There are two basic ways that a material in a mattress reacts to weight and pressure.

  1. Viscous materials tend to flow away from pressure like a liquid or honey and tend to distribute and absorb energy

  2. Elastic materials tend to store energy under pressure and to different degrees push back against compression

Materials in a mattress that absorb compression forces and redistribute pressure away from pressure points are great for pressure relief but not usually as good for support. Layers that store energy and push back can also be very good at pressure relief in softer versions but are also better for support. This also depends to some degree on the point elasticity of the material and its ability to form a conforming cradle that mirrors the shape of the body. All viscous materials are good at this. Some elastic and more resilient materials are better at this than others. The different layers in a mattress are usually designed in such a way that the complete mattress will have both supportive qualities and pressure relieving qualities. The core of the mattress which is the middle and bottom parts (usually innerspring, latex, or higher quality polyfoam) is the part that is primarily responsible for supporting the heavier parts of your body and keeping them from sinking in too far. The comfort layers which is a few inches (usually polyfoam, latex, memory foam, natural wool, horsehair, or synthetic fibers) are responsible for redistributing pressure so you don't get "pressure points" when you sleep. They are also responsible for supporting the inner or more recessed parts of your body (like the small of your back, waist, upper thighs, etc) so that gravity doesn't pull them down against the natural position or curvature of your spine. These parts of your body don't usually sink in enough for the deeper support layers to truly support them.

So what does all this mean in mattress terms?

Its unique combination of qualities leads to the advantages of memory foam for some...but the same combination of qualities that are attractive to some can also be responsible for memory foam's weaknesses for others ...

So there you have it. Hopefully I have covered the main points of the generic differences, strengths, and weaknesses of memory foam as a whole. In my experience and research, memory foam has been the subject of more misinformation and hype than almost any other material in a mattress and this confusion and misinformation has in my opinion led to too many poor or at least inappropriate mattress buying decisions. It is sometimes a frustrating process to "get to the bottom of things". Memory foam is certainly a valid choice in a mattress material for some people and there are many who love it however I believe that knowing more about what it does in comparison to other materials and why and how it does it, is an important part of buying a memory foam mattress. There are many choices of mattress construction available and the more those choices are based on fact, personal experience, and individual needs and personal preferences, the more likely you will be to buy a mattress that is perfect for YOU.

Log in to comment

TD Bauer's Avatar
TD Bauer replied the topic: #2 24 Apr 2017 11:25
Great article on the Pros and Cons of a memory foam mattress. I depend heavily on consumer reviews when I buy most things for the home, and mattresses are no different. Lots of good information here, especially if the person or place selling you the mattress can't tell you the various issues you may face with a memory foam bed.

TD Bauer
phoenix's Avatar
phoenix replied the topic: #3 25 Apr 2017 09:19
Hi TD Bauer,

Great article on the Pros and Cons of a memory foam mattress.

Thank you. I’d like to think so. ;)

I depend heavily on consumer reviews when I buy most things for the home, and mattresses are no different.

“Review” sites (most of which are really “revenue” sites) are generally the absolute least reliable way to choose a mattress, and if you “depend heavily” upon them to make a purchase, I would suggest you hit “reset” on how you are going about selecting a mattress, as it's not possible for a review site to make specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first "rule" of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best "match" for you in terms of "comfort", firmness, or PPP or how a mattress will "feel" to you or compare to another mattress based on specs (either yours or a mattress), sleeping positions, health conditions, or "theory at a distance" that can possibly be more reliable than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial ) or your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here ).

People are also very different and if you choose a mattress based on the premise that "many people seem to like this type of mattress so I will probably like it as well" it can create unrealistic expectations because any individual (and for that matter most individuals) may be very different from the "average" of a group in terms of their body type, sleeping positions, and preferences and there is no way to know whether the specific mattress they are considering was even included in the group or has any weight in the results.

You can see my comments about many of the so called "review sites" which are mostly just revenue sites that know little about mattresses or mattress materials in post #11 here and in posts #4 and #6 here , many which don’t provide any particularly meaningful or accurate information and instead depend upon traffic and backlinks to build SEO and income.

A big part of the underlying problem with these types of marketing systems is that consumers as a whole put too much trust in mattress reviews in the first place (either positive or negative) in the mistaken belief that they are a good way to assess whether a mattress would be a suitable or a durable choice for them so they end up choosing a mattress for all the wrong reasons based on other people's experiences and reviews or on the "deal" they think they are getting instead of legitimate "fact based" research that would be relevant to their own unique needs, preferences, and criteria. This is more of an issue with consumers in general that can really only be solved with education about how to buy a mattress.

The goal of this forum has always been to help educate and inform and to help people identify the criteria that are most important to them and to help with "how" to choose, not "what" to choose, and this way they can be well on their way toward making an informed decision when considering memory foam mattresses, especially those imported from Asia or China (read post #6 here ) which may have been compressed for long periods of time in either shipping or storage before being purchased and would make this somewhat of a risky purchase IMO.

msully's Avatar
msully replied the topic: #4 04 Mar 2018 12:10
I wish I had found this article a few years back. I've gone through 4 mattresses in the past 5 years (2 purchases, and 2 'free replacements'). Two of them were firm mattresses with memory foam cushions. They felt great in the store and when I first went to bed, but half way through the night, especially in the summer, the memory foam under me had compressed to almost nothing, leaving me sleeping (uncomfortably) on a just the firm layer underneath.
The latest has memory foam further down and unsurprisingly (after reading this) also softens overnight leaving an even worse uneven sleep surface.
I wanted a mattress with no memory foam with my last replacement but the mattress store insisted all of their mattresses had at least some memory foam in them. Never going back there.
Hopefully the information on this site will help me find a new one that is comfortable throughout the night, especially since I incline it for reflux. For now I need to take a break since the 4 hours of sleep I got last night are making it difficult to focus on all of these details.
HuskyHawk's Avatar
HuskyHawk replied the topic: #5 04 Mar 2018 12:27
Thanks for this. Considering our first memory foam mattress (at least partially memory foam) and I have some misgivings. I tend to sleep hot in summer. Plus I tend to move a lot (wife does not). But we need some significant pressure relief as side sleepers (one with shoulder issues).
phoenix's Avatar
phoenix replied the topic: #6 05 Mar 2018 11:58
Hi HuskyHawk.

Considering our first memory foam mattress (at least partially memory foam) and I have some misgivings. I tend to sleep hot in summer. Plus I tend to move a lot (wife does not). But we need some significant pressure relief as side sleepers (one with shoulder issues).

I understand your “misgivings” about Memory foam .... while it does a very good job at minimizing motions transfer it will generally be the least breathable and most insulating of the foam comfort materials, so temperature can be an issue. There is a little more about the Memory foam in this article here In general terms Memory foam has very low resilience, has a more "in the mattress" feel to it, and changes its feel and response with pressure, temperature, humidity, and length of time it is subject to compression forces. It can feel firm in some conditions or circumstances and soft under different conditions. (As you've already seen in the pros and cons of memory foam article :)

As far as the shoulder pains...first off, I’d make sure that you reevaluate your pillow to make sure that it is providing a decent alignment to keep your cervical/upper thoracic region in a relatively neutral arrangement. Improper pillow thickness is a common cause for shoulder issues, especially with a new mattress.

You may be looking in to the right direction with something plusher as you are both side sleepers and one of you has shoulder issues, which usually come from a mattress that is too firm and puts direct pressure on the shoulders, the shoulder blades, or on the back muscles and can also cause soreness or numbness and tingling in the arms or can often come from postural issues as well. If the mattress is too firm then if you sleep on your side your shoulders may not sink in enough to relieve pressure and your upper body can "twist" away from the pressure so your upper body is "twisted" more forward while the lower body is still on its side. This spinal twisting or torsion can twist the spine in the upper body and lead to soreness in the area of the twist. There is some much more detailed information on shoulder and arm issues in posts #2 and #3 here


Latest Posts

The Mattress UndergroundCopyright © 2022 The Mattress Underground