What is Memory Foam? Here’s How it Works and the Pros and Cons

Not too long ago, memory foam didn’t even exist. And now, these mattresses command an impressive 46.87% market share.

An aging population, a rise in the number of sleep disorders, and the convenience of buying furniture online have all contributed to this material’s rapid growth in popularity. In 2004, these beds accounted for only 14% of the mattress market. That number has more than tripled over the past decade.

You might not know a lot about memory foam other than a faint recollection of those old Tempur-Pedic commercials showing people’s hands sinking into a piece of foam. When the person removed their hand, television viewers watched in awe as the material continued to show the imprint of the hand.

Given its popularity and wide price range, you might be wondering what all the fuss is about and if your next bed should be this material. We’ll provide the information you need to decide if a new bed made from this unique foam could be right for you.

What is Memory Foam Made of?

Memory foam is polyurethane combined with some chemicals that allow it to contour to your body. It’s also called viscoelastic, which combines two concepts: viscosity and elasticity.

  1. Viscosity – the material moves slowly and reluctantly when pressure is applied. Honey is an example of something that is viscous.
  2. Elastic – the ability to stretch and change shape while still returning to its original form.

When you combine these two properties, you get something that contours to the shape of your body, hugs your curves and makes you feel like you’re sleeping on a fluffy cloud. Then, when you get up, it returns to its normal state after you no longer put weight on it.

The viscoelastic foam was originally developed by NASA scientists in 1966. They put it in seatbelts and harnesses to make space travel safer. The general idea was that the turbulence and impact felt when traveling at such fast speeds would be tolerated better if the equipment was padded and designed to absorb impact.

It wasn’t long before some industries realized the potential for this material. It was adopted in hospital settings to keep immobile patients comfortable, and it also became popular in wheelchair seats. Finally, in 1992, a new company decided to sell this material commercially in the United States.

Tempur-Pedic was born, and at first, they only sold two products. One was a 3-inch Tempur-Pedic mattress topper, and the other was a neck pillow. They only sold 70 mattress toppers their entire first year in business, but it’s a good thing the company kept at it because they revolutionized the way we sleep.

Different Types


The first type introduced to the market was traditional memory foam. It molds to the contours of your body and envelops you in a hug while you sleep. It’s notorious for causing people to feel like they’re “sleeping hot,” so now many brands take steps to make sure that product helps the sleeper stay cool.

Get More Info: Top Rated Memory Foam Mattress

Open Cell

To combat the heat of the traditional variety, open cell foam was invented to help people stay cool. The interior structure has pockets that allow for airflow. On the plus side, sleepers won’t get so hot, but the holes mean that the surface of the bed is less dense. It’s often a lesser quality material that won’t last as long.


This type of foam has been filled with gel, often in a beaded form. Gel has natural cooling properties, so it can help regulate your temperature as you sleep. There are two types of gel available:

  1. Heat absorbing gel – it creates a cool surface that prevents overheating.
  2. Phase-changing material – it allows the body temperature to remain constant by releasing and absorbing heat.

Gel isn’t the only cooling additive that companies have implemented to make their product even better. In addition to gel infusions, you may also encounter copper and even aromatherapy scents like lavender.

Some companies also use layers of corrugated foam, which is also called “egg crate foam” because it resembles the inside of an egg carton.

gel memory foam


Pain Relief

Memory foam is known for helping with pain. It’s a top choice among people with arthritis and people who have fibromyalgia because it best simulates the feeling of sleeping on a fluffy cloud. The contouring also helps to keep the body in a natural alignment, which we’ll get to in a moment.

If you’re the type of person who struggles to get comfortable on a traditional mattress, or you have a hard time finding an ideal mattress firmness level, then you’ll probably appreciate this material.


There aren’t many places for mold, pollen, dust, and pet dander to hide in this dense of a mattress. This is ideal for allergy sufferers. Also, the components are usually made of things that don’t trigger allergies. There’s no wool, feathers, etc. So, if you’re allergic to these things, you may rest better on this surface.

Other types of mattresses have excess air pockets and space between coils that allow for moisture and mold buildup. They can serve as a breeding ground for dust mites. With a memory foam mattress, routine care like vacuuming and an occasional sprinkling of baking soda will allow it to remain a safe haven from allergies.

Pressure Point Relief

Pressure point relief has become something of a buzzword in recent years, but for good reason. And this is where viscoelastic beds shine.

Think of it this way: what happens when you lie down on your side on a slab of concrete? You’ll probably feel the ground digging into your hips, your arm will fall asleep within minutes, but you’ll be lying there, wide-awake, wondering why you’re lying down out in the street.

Because viscoelastic contours to your curves, it takes the pressure off your denser and heavier body parts like the hips and shoulders. This discovery was what gave this material its start in hospitals. Not only did it help patients sleep more comfortably, but it also worked to prevent things like bedsores.

Back Support & Spinal Alignment

When you lie down, your spine should maintain a similar position as when you’re standing. When people sleep on the wrong surface, their spine tends to jut out or collapse in at unnatural angles. If you wake up sore or stiff in the morning, it could be your mattress’s fault. However, with memory foam, the contouring effects allow the spine to maintain its natural shape.

The best way to test your bed to see if it allows for proper alignment is to lie down on your side and have someone take a picture of you from behind. If you’d prefer to work alone, then set a timer on your smartphone’s camera and take a picture that way.

Then, take a look at the angle of your spine. It should be a nearly perfectly horizontal line. If your hips and shoulders are raised up or sinking down, then you know it’s time for a different bed.

People looking into this type of mattress should make sure they get one that has the proper density. If it’s too firm or soft, you’ll miss out on the benefit of proper spinal alignment. As a general rule, the higher the foam density, the firmer the mattress. All mattress companies and web sites will specify what the density specs are. Look for something that’s at least 3.5, if not closer to 5.0.

Want to know more? Check out our complete mattress firmeness scale and guide here.

doctor is checking spine of a woman

Good for All Sleeping Positions

Memory foam’s contouring and cradling properties make it an ideal surface for all sleeping positions. Side sleepers get support in their hips and shoulders; back sleepers get lumbar support; and, stomach sleepers are less likely to have their low back bow into the bed.

Many people are combo sleepers, meaning they sleep in two or more positions during the night. The beauty of this material is that since it accommodates all of those positions, you don’t have to make a choice that would compromise your ability to sleep on your stomach, for example.

This means it’s also an ideal mattress option for couples. If one of you sleeps on your side, while the other partner is a back sleeper, then viscoelastic helps you reach a compromise that you’ll both be happy with.

Motion Isolation

One of its best features of viscoelastic is that it doesn’t wake your partner if you’re tossing and turning. You’ve probably seen commercials where a glass full of red wine rests on one side of the bed while someone jumps up and down on the other side. Miraculously, the wine doesn’t spill.

This miracle is due to the fact that the material absorbs pressure and movement. Instead of bouncing like innerspring or latex beds, this one stays put.

Dust Mite Mitigation

You’ve probably heard stats about millions of dust mites creating colonies in the depths of some mattresses. A lot of people are allergic to the fecal matter of dust mites, which could make them feel miserable every time they go to sleep.

Fortunately, the density of the material in these beds means that there are fewer places for them set up shop. Memory foam is also anti-microbial, which makes it a less hospitable environment for unwanted critters.

Fit for Adjustable Beds

Adjustable beds have grown in popularity recently. They allow sleepers to adjust their positions to help with sleep apnea and they’re great for watching television or reading in bed. Many newer models also have electronic integrations and massage capabilities!

Sometimes, it’s hard to fit a bed to an adjustable base because the compressing and bending that happen can ruin a mattress or at least decrease its lifespan. Memory foam beds are flexible enough that they can sit on nearly any surface without compromising the bed itself.


A quality mattress can last about eight to ten years. Because the foam can bounce back to its original shape, these mattresses tend to have a longer useful lifespan. Again, look for mattresses that have a higher density, as these tend to last longer and won’t sag over time.

Learn More: View Our Complete Memory Foam Density Guide

Also, check the warranty before you buy because some companies offer a lifetime warranty!

blue and grey bedroom



We’ve already discussed the heat element, and that’s probably the most significant complaint among viscoelastic mattress buyers. However, many homes have the ability to adjust the room temperature with a thermostat or air conditioner, and anyone can switch to lighter bedding if they get too hot. Given that reality and the fact that new innovations have been made to diminish the heat, we think this “con” is avoidable.


Although dense foam tends to be of higher quality, it does make for a heavier mattress. Luckily, the industry has changed significantly over the past few years. Many of these beds now come compressed in a box and are easier to transport than other types of beds. You’d be surprised by how small some of those boxes are!

Not Water Resistant

If you sweat, spill a beverage or have an accident, then beware because these mattresses aren’t waterproof. We recommend protecting your investment with a waterproof mattress protector. Many of these enhance the sleep experience by contouring to the mattress, whereas older versions used to be plastic and uncomfortable.


People who order beds online sometimes complain about something called off-gassing. This is when the VOCs (volatile organic compounds) break down when exposed to air and create a distinct odor. New car smell is one type of off-gassing from VOC’s, although most people find that scent pleasant.

While there have been no studies linking these odors to any long-term health risks, some people have allergic or respiratory reactions. Our advice is to let your new bed air out for a couple of days until the smell dissipates.

If you’re concerned about off-gassing, look for a plant-based mattress brand. Because of the plant material, there will be little or no odor. Higher quality brands also tend to produce less of these odors. We’ve found that a helpful way to determine if your mattress of choice will have an odor is to read the reviews online before you buy. People are really passionate about this topic and will let you know through their reviews how the mattress performs in this area.


Top quality mattresses, especially those with the Tempur-Pedic brand name, can cost thousands of dollars. Aspiring businesses saw an opportunity and began selling reasonably priced beds over the Internet. Now, for around a thousand dollars, you can get a bed fit for a king.

By cutting out the middleman and selling direct to the consumer, these companies allow you to get a quality bed at a fraction of what you’d pay at a showroom.

tempur pedic memory foam bed

Frequently Asked Questions

Do you recommend it for back pain sufferers?

How long does memory foam last?

The lifespan of this product depends on a couple of factors.

  1. The density of the foam. Viscoelastic foam is classified with a density rating measured in cubic feet with 1.5 being the lowest and 8 being the highest. As a rule, the lower the density, the softer the surface and the lower the quality. The concept of diminishing marginal returns does apply, where a higher number yields little or no extra benefit.

In general, the beds that will last the longest and be the most comfortable have densities ranging from at least 3.5 to 5 or 5.3.

  1. Your size and weight. Heavier people will wear out a mattress faster. Gravity and pressure cause the materials to sag in a shorter timeframe than would happen with a lighter person.

So, to answer the question, our estimation is 4-6 years for a low-density foam, and 8-10 years for high-quality and high-density foam.

Is it safe or toxic for children?

Memory foam is generally considered safe and non-toxic for people of all ages. However, kids may be more sensitive to the chemicals used to make and treat the mattress. They might experience allergies, asthma, headaches, breathing difficulty, coughing or nausea.

Because of the extra time that children spend sleeping and the fact that their biological systems are still in development, you may want to seek out a more natural alternative if you’re concerned about an allergic reaction. There are organic mattress alternatives available that could be safer.

Also, be on the lookout for mattress certifications for assurances that the bed is free from harmful chemicals. Some to look for include Oeko-Tex and GreenGuard Gold. If the mattress you’re evaluating has certifications like these, then they’re likely to be safe to use for anyone.

Read More: Is Memory Foam Toxic?

What is a good memory foam pillow?

Pillows are a highly personal choice, but we believe you can’t go wrong with a Tempur-Pedic memory foam pillow. A word of caution, though. They’re not cheap. Many mattress companies make their own pillows, so if you’ve found a brand of beds you like, you’ll probably sleep well on their pillow, too.

We also like a couple of brands that allow you to add and remove foam so that you can customize the size and shape of your pillow.

Check Out Our Guide: Best Memory Foam Pillows

Our team covers as many areas of expertise as we do time zones, but none of us started here as a so-called expert on sleep. What we do share is a willingness to ask questions (lots of them), seek experts, and dig deep into conventional wisdom to see if maybe there might be a better path towards healthy living. We apply what we learn not only to our company culture, but also how we deliver information to our over 12.7M readers.

Sleep research is changing all the time, and we are 100% dedicated to keeping up with breakthroughs and innovations. You live better if you sleep better. Whatever has brought you here, we wish you luck on your journey towards better rest.

Sleep Advisor