What Is Memory Foam?

written by sleep expert Lauren Hall
What Is Memory Foam? Everything You Need To Know:
If you’ve been looking for a new mattress for a while, you’ve probably heard of the term “memory foam.” Memory foam has taken the world by storm, and it is now rated one of the most comfortable mattresses on the market; its conforming capabilities are a real hit.
It was first created by Nasa back in the 60s to offer pressure relief and shock absorption when exiting and entering the earth’s atmosphere, but since then, it has been introduced as a mattress material and imploded the market and advancing over the years with new technology.
But what is a memory foam mattress anyway? What is memory foam made of? Why should you choose memory foam?
I’m going to run through everything you need to know about memory foam and everything you need to look out for before taking the plunge– including the pros and cons of memory foam. It is brilliant for those with back and neck aches and those looking for pressure relieving qualities.
That being said, anyone can benefit from using a memory foam mattress; it can seriously improve your quality of sleep and leave you feeling well-rested, rejuvenated, and ache-free when you wake up in the morning– it is also brilliant for couples as it absorbs movement in the night.
So stay tuned; I’m going to break down all the ins and outs of memory foam along with how to buy the best memory foam mattress on the market.

What Is Memory Foam Made Of?
Before we dive into everything you need to know about a memory foam mattress, let’s skip back to the basics. What is memory foam, and what is memory foam made of?
The main component that makes up memory foam mattresses is a polymer called polyurethane; it is an extremely versatile plastic polymer that is used to create a wide range of materials and products, including furniture like sofas and mattresses.
It can even be used to create insulation, liquid paints, primes, spray foams, and even car parts– told you, it was versatile!
Memory foam is known as viscoelastic polyurethane foam or low resistance polyurethane foam; it is created by adding various compounds and additives to polyurethane depending on what type of memory foam is being created.
The chemicals used to create the foam can affect viscosity and elasticity. The viscosity is how long it takes to change shape under pressure or to transfer energy from one place to another, while the elasticity is the stretch, contouring and whether it will return to its original shape after the pressure is taken away.
Different manufacturers have different recipes of chemicals they add to the foam, but the most common type of memory foam used in memory foam mattresses is viscoelastic foam which helps with the elasticity of viscosity,
NASA first created the viscoelastic foam in the 1960s to counteract the extreme pressure which astronauts faced when exiting and entering the earth’s atmosphere, and now it has taken the bed market by storm with mattresses, pillows, and even mattress toppers.
The type of material and chemical used has a lot to do with how most memory foam mattresses come out; the manufacturing process has a lot to say about the quality. Many cheap brands use cheaply made memory foam which won’t last more than a couple of years.
How Does Memory Foam Work?
Memory foam is designed to slowly mold around your body in response to pressure on the mattress; it works to evenly distribute body weight and conform to your body’s shapes and curves. Once the weight and pressure have been lifted, memory foam is extremely resilient, so it will return to its normal shape.
Memory foam tends to respond slightly differently depending on how you apply pressure on the mattress. If you apply pressure quickly, then memory foam mattresses tend to change shape slowly, making this material ideal for absorbing impact.
This also makes it ideal for couples as it absorbs vibrations and sounds like one person tosses and turns, causing minimal disruptions.
Memory foam cushions and contours your body’s shapes and curves as the mattress adapts to the impact of your body and cradles each shape and curve to relieve pressure and provide comfort. It can offer some serious relief for aches and pains such as back, hip, shoulder, and neck pain.
As memory foam heats up, it becomes more flexible, which is why memory foam mattresses feel softer and more pliable after you’ve been lying on them for a while since your body heat increases the temperature of the sleep surface.
It does have a tendency to sleep hot, which is why it is often infused with gel or a natural cooling material to help dissipate heat and keep heat away from your body, so the temperature remains neutral as you catch some serious Zzz’s.

Types Of Memory Foam Mattress:
When buying memory foam mattresses, there are three common types you’ll come across; these basic types are constructed slightly differently with different compounds and processes in order to create the mattress.
Traditional Memory Foam Mattress:
This is also known as the regular, original, “classic” memory foam. It was the first memory foam created and the original design by NASA. Traditional memory foam conforms and molds around your body and works to relieves pressure points to help relieve aches and pains.
Traditional memory foam is known to sleep hot and trap heat, so while it offers serious benefits for back pain and offers some serious comfort, newer designs have been created to combat this heat issue so people can rest comfortably.
Gel Infused Memory Foam Mattress:
The most common type of memory foam is gel-infused memory foam which is used in many memory foam mattresses. Gels are often infused into the internal structure by pumping gel-based microbeads into the foam. These microbeads work to create pockets within the foam.
Gels are often “phase-changing” materials that actively absorb and release heat from your body. Some gels will cool you down until you reach a certain temperature and then help maintain that temperature.
But gel is not the only infusion found in memory foam mattresses; copper is another popular choice commonly used by memory foam manufacturers. Copper is highly conductive and helps disperse heat, and is extremely moisture-wicking in comparison.
Some modern mattress companies incorporate gel and copper infusion within their memory foam design along with using an open cell foam to help dissipate heat, regulate temperature and airflow within the mattress.
Open-Cell Memory Foam Mattress:
Open-cell memory foam tends to use the same ingredients as traditional memory foam but uses an open cell structure which helps give these memory foam beds more of a breathable feel. The open-cell foam tends to have internal pockets to allow ventilation within the mattress.
This airflow is really effective paired with a gel as the gel can help disperse body heat and draw heat away from the body, while the open-cell design can help ventilate airflow to help keep the body cool.
Older open-cell designs had a very dense foam and were a lot less supportive than any other memory foam mattress type, but as technologies have improved, open-cell constructions made the sleeping surface much softer and more supportive, offering efficient spinal alignment.
Memory Foam Mattress Construction:
Memory foam mattresses tend to have a different internal structure to other mattresses, and different memory foam mattresses have different constructions to achieve specific qualities like cooling. However, most memory foam mattresses follow a basic construction in their design.
Comfort Layer: Many mattress companies start off their quality bed with a comfort layer of memory foam. These are often contouring and cushioning, depending on the level of firmness. Higher-density memory foam tends to be much firmer than a thinner layer.
Many mattress companies use a breathable foam in this layer to help draw heat away from the body and the sleeping surface. Some even infuse gel memory foam for this layer to help with the cooling capabilities of the foam.
Transition Layer: After the comfort layer, there tends to be a transition layer which is made up of one or more foam layers. It tends to be firmer than the comfort layer but not as firm as the core. It adds stability to the mattress, so you don’t sink too deep into the memory foam.
Cooling technologies also tend to be used in this layer to help wick away heat from the comfort layer. This prevents retaining body heat within the memory foam and helps with the cooling effect of the mattress.
Copper or gel is often infused within this layer to work with the comfort layer; the comfort layer is often ventilated, so it helps when dissipating body heat.
Core: The core is the base of the mattress; it is often composed of a much firmer, higher-density memory foam. It is also the thickest layer out of them all; it supports all the layers of memory foam and prevents you from sinking too far into the matters.
It also tends to provide additional support. Some hybrid mattresses have memory foam layers n top, and the core is made from innerspring, which provide extra support, bounce, and ventilation to the mattress. If you sleep hot, this is a great alternative!
It uses the combination of memory foam and an innerspring mattress within the structure.

Memory Foam Mattress Pros And Cons
Memory foam mattresses come with their fair share of pros and cons, and some of these come with the memory foam mattress cost. As a general rule of thumb, the more you spend, the more benefits you get from the memory foam.
Memory foam is a bit like marmite; some people love it, some people hate it. There are some common benefits of memory foam, while there are some drawbacks. So let’s talk about the pros and cons of a memory foam mattress.
Benefits Of Memory Foam Mattress:
So there are many benefits of buying a memory foam mattress, and it can really induce a good night’s sleep if it’s the right fit for you, so here are the pros of a memory foam mattress.
Pressure Relieving:
Memory foam contours your body, and from the heat of your body, it molds to your body’s shapes and curves to cradle your shape and lift pressure points. This offers superior pressure relief in areas like your hips, shoulders, neck, and back.
By sleeping on a poor mattress, it can cause aches and pains when you wake up; it also causes trouble when trying to fall asleep, which often leads to tossing and turning and restlessness. The continuing qualities of memory foam can help reduce pain and discomfort by evenly distributing weight.
This takes the pressure and stresses off of common pressure points, which allow you to fall asleep with ease. Also, by memory foam effectively cradling your body, memory foam also relieves pressure no matter what sleeping position you’re in.
So no more tossing and turning to try and find that “sweet spot,” every position will be that sweet spot, my friend.
Promotes Effective Spinal Alignment:
Because of memory foam’s contouring capabilities, this helps promote good spinal alignment along with providing lumbar support. The surface responds to your body’s natural curves, making it easier to find a sleeping position that supports your spine and keeps it neutral.
This also prevents restless tossing and turning in the night as well as back pain and soreness in the morning. You’ll wake up feeling as fresh as a daisy!
Hypoallergenic:
Memory foam is an ideal choice for those with allergies because memory foam mattresses tend to be hypoallergenic; the dense structure of the memory foam makes this mattress less likely to attract and accumulate allergens such as dust, mold, and irritants.
Pairing a memory foam mattress with a mattress protector or mattress pad will help reduce this by up to 60% against infestations and 80% against dust mites! So if you’re thinking of getting a mattress protector, I would 100% recommend it– it is an ideal choice for hot sleepers too!
Knowing how to clean your memory foam mattress is also crucial if you have allergens, as while memory foam mattresses are hypoallergenic, they need regular cleaning to prevent infestations.
Reduces Motion Transfer/Noise:
For couples, a memory foam mattress is an ideal choice, especially for light sleepers, as memory foam will absorb the motion of tossing and turning or if your partner moves or gets up in the night. This means fewer disturbances and more chance of getting a quality night’s sleep.
Memory foam has a slight advantage over innerspring mattresses or even hybrid mattresses because of the density of the foam and the way it responds and evenly distributed weight; it keeps moving on one side of the bed without being felt on the other.
So that being said, memory foam mattresses are also known to be very quiet, which is another important factor for couples who don’t want to disturb their partner in the night or if they need to wake up early in the morning.
Plus, there’s no squeaking or groaning with every move. Unlike some spring mattresses, you can toss and turn in complete silence, making it much more comfortable for those who sleep in different sleeping positions throughout the night.
Memory Foam Mattress Cons:
But with every mattress with the pros, there are always some cons that follow; I don’t think there is a mattress on the planet that is faultless… yet! So here are the cons of a memory foam mattress.
Retains Heat:
One of the top drawbacks of memory foam mattresses is that they retain heat within the mattress. Memory foam is known to trap heat and become uncomfortably hot. Since memory foam responds to heat and because of the density of the foam, memory foam can get quite hot at night.
But because of this reason, scientists and mattress manufacturers desperately sought for solutions to tackle this issue which is where the gel infusion and open-cell design comes in. There are many infusions you can add to the memory foam mattress, but they still sleep hotter than a traditional mattress.
So if you’re a hot sleeper, then buying a memory foam mattress is not recommended.
Cost:
This technology within the memory foam mattress also comes at quite a steep cost. Often much pricier than other mattresses as you need to buy higher quality memory foam mattresses in order to get the most out of these cooling technologies.
But many mattress companies are now offering the mattress-in-a-box, which helps combat this high price tag because the popularity, as a result, has gone up, so the higher demand means the lower the price.
But when buying a memory foam mattress, it needs to be an investment, there’s no point buying a cheap mattress and then a couple of years down the line have to buy another one as it has sagged or just doesn’t perform as well as it used to– may as well have paid out a little extra for high-quality components.
Sinking Feeling:
For many cheap memory foam beds, there often isn’t enough support in the base layer leaving people feeling like they’re sinking into the mattress, giving the feeling of being stuck or sucked into the material.
This makes moving in the night much more difficult, plus many people who are claustrophobic find this off-putting as you won’t feel comfortable in the night. Plus, this sinking feeling will be even worse as the mattress ages as the bounce back will begin to wear.
This is also why it’s important to invest in a mattress with many layers and with a high-quality base layer; this will prolong the life of the mattress and protect this. But for this reason, many people opt for a hybrid mattress instead as the springs tend to have much more bounce and support as well as last longer.
The springs/coils also make the mattress feel softer, so you can have the conforming capabilities of memory foam but the support and bounce of the innerspring.
Not Waterproof:
Since memory foam is like a sponge, it means it can be easily damaged by water; water can sink through the layers, which will not only degrade the foam but also make it the perfect breeding ground for mold and infestations within the mattress.
Liquids, in general, can reduce the lifespan of a memory foam mattress; they’re not ideal if you live in a high-humidity area or have a young child or pet that is prone to accidents or spillages– especially not recommended if you have a toddler going through potty training.
Regular cleaning of your memory foam mattress is also important, but don’t worry since you can’t really get the mattress wet I have broken down how to clean a memory foam mattress in a full article so be sure to check it out.
Bad Odors:
For the first few weeks, memory foam mattresses tend to give off an off-gassing odor which has a distinct chemical-like smell. The smell does tend to go away 24 hours after unboxing, which is the usual time it takes to inflate anyway but can be around for weeks.
Memory foam mattresses that are made cheaply or have a cheap price tag tend to have a bad smell that can last for weeks– not fun.
Heavy:
A memory foam mattress is a much heavier mattress than any other type, many companies that sell their mattress online vacuum pack the mattress in a box to give the illusion that they’re lightweight, but in most cases, this isn’t true.
Plus, once it has been inflated, it tends to be even heavier, so it’s best to roll onto the bed and leave it to inflate, so you don’t need to do any more heavy lifting after getting it out the box– you’ll thank me later.
Plus, if you have a queen-size mattress or even bigger a California king, then I would recommend changing your sheets with your partner as lifting the bed will be quite a challenge in itself. Plus, if you decide to change rooms, then bear in mind moving the mattress out of the room will be more difficult than bringing it in.

Things To Look Out For When Buying A Memory Foam Mattress:
Now down to the buying process, there are a few things you should consider or look out for when buying a memory foam mattress, especially if you’re buying online. This will ensure you’re getting the very best deal for the money.
Density:
When you’re shopping for a memory foam mattress, one of the things you need to look out for is is the density of the memory foam. The density of it helps you to determine how soft or firm the mattress in question is.
Let’s imagine you’re walking around a mattress store, looking for one that is reasonably firm.
Rather than lying on every single mattress you can find, knowing that a medium density mattress comes with 4 -5 pounds of memory foam per cubic foot can help you to quickly determine if that mattress is right for you.
Low-density mattresses usually come with less than 3 pounds of memory foam per cubic foot, and high-density ones usually come with six or more, depending on the manufacturer.
So, try out a few beds, see which one you prefer the most, and note the density. Now you’ll be able to walk around the store or shop online for a mattress that’s as firm or as soft as you would like.
You should be aware that the higher the density of memory foam, the longer yours is likely to last, simply because it contains more memory foam. This means it may be worth your while buying a mattress that’s just a little firmer than you would usually buy.
Firmness:
Memory foam mattresses come with a wide range of different firmness levels; it is often described on a scale from very soft to very firm– usually on a scale of 1 to 10, with one being very soft and ten being very firm. The firmness is really down to your personal preference for sleep.
Think of Goldie Locks & The Three Bears; everyone likes something different.
Most mattresses will come with an Indentation Load Deflection (ILD) rating, which measures the firmness; the higher the ILD rating, the firmer the mattress will be; each layer has its own ILD score, and then the mattress as a whole will have one.
So if the mattress has an ILD score of 10, it will be very soft, and if it is at 50, then it will be very firm, so if you want something in the middle, judge it through the ILD rating. As a general rule of thumb, the thicker the mattress, the more firm it will be.
You should also consider your body weight when choosing a firmness level. If you are on the heavier side, you might want to get a firm mattress as otherwise, you might sink into the mattress if it is too soft.
Cooling Technology:
Since memory foam mattresses have the tendency to sleep hot, it is important that you invest in good quality materials that offer efficient cooling technology. Most mattresses nowadays use an open-cell design with some form of cooling infusion to help tackle heat at night.
Most infusions are either some form of cooling gel or infused copper into the mattress, which helps draw heat away from the body as well as regulate body temperature. So it works to cool your body to a certain temperature and then keep your body at that temperature throughout the night.
The cooling technology has really advanced in recent years– it’s pretty impressive if you ask me!
Sleep Trials & Warranty:
These factors are super important when buying a mattress, and sleep trials are especially important when buying a memory foam mattress online; it gives you the leniency to change your mind if it’s not quite the right fit for you.
Most companies offer at least a 30-day sleep trial, while others are more generous and offer a 365-day sleep trial (like Nectar) but are sure to read the fine print to make sure you’re not caught out with hefty return costs, as some companies will hide this in the fine print.
If you would like your purchase to be protected, you may want to take a look at the manufacturer’s warranty. A warranty works as a guarantee that the manufacturer will repair or replace the mattress should a fault develop with it.
The warranty is usually available within a specific period of time (Often 10-25 years for mattresses), and you’ll also find there are specific conditions included. This means that you may not be covered for spilling red wine on your nice new one, but you could be covered if the mattress doesn’t work as well as it claims to.
If you would like to make a claim on your warranty, you will have to check the details first, as there will be specific conditions.
The warranty also gives you an idea of how long the mattress will last you. If the warranty is around ten years, you can expect to get that much out of the mattress, and if it doesn’t meet those standards, then many companies offer a refund or replacement.

Final Thoughts
So there you have it, everything you need to know about memory foam mattresses. If you’re planning to buy a memory foam mattress for your back pain, I would highly recommend it! Make sure you weigh out the pros and cons before you purchase.
It is also essential to set a lenient budget and do your research on different brands; you’ll want to find one that best suits your wants and needs while remaining on an excellent friendly budget. Memory foam mattresses are an investment, but they’re worth it.
If you want the conforming capabilities of memory foam but find that you’re quite a hot sleeper, check out my hybrid mattress guide as they are the best of both worlds; they have the benefits of memory foam, but the cooling capabilities and ventilation off innerspring mattresses.
But also check out my memory foam vs hybrid mattress guide too if you want to weigh out the key differences between the two before you choose.
Happy shopping, my friends!
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