Memory foam was first created by NASA in the 1960’s. It wasn’t until Tempurpedic came along that memory foam really became popular in mattresses. After the success of Tempurpedic, many manufacturers started using memory foam in their mattresses. Compared to traditional innerspring mattresses, memory foam mattresses stood out because of their ability to reduce pressure points and increase overall comfort. The sleeping experience on a memory foam vs innerspring mattress is truly different. Generally, memory foam mattresses are quite popular, but they aren’t for everybody and many brands do come with common complaints, such as sleeping hot and softening over time. Here I will review memory foam mattresses as a category and go through the most important pieces of information you should know to help you find the best mattress for your needs.
Price Difference Explanation
If you look through the product line available for memory foam mattress manufacturers, you will see a wide range in the prices for their products. The wide price range has any of several explanations. A few of them are as follows:
Density- Higher-density foams are almost always more expensive. The materials used to make the mattresses are more costly and the value received by the customer overall tends to be higher with high-density foams.
Thickness- Thicker mattresses generally cost more. The materials cost to make them is higher and the mattresses that are thicker tend to be more supportive. Higher-priced mattress tend to have memory foam make up a greater percentage of the overall thickness of the mattress (the base layer in these mattresses is normal foam with memory foam on top).
Materials- Not all memory foam is constructed in the same way. As I note elsewhere, some mattresses are gel-infused to help keep the mattress cool. Others actually have a gel layer to further make the mattress stay cool. Some memory foam is constructed using a portion of bio-based oils. This more eco-friendly solution is much more costly to the manufacturer, which normally means a higher price tag for the consumer.
Good Marketing- Some mattresses are more expensive simply because the company making them spends a lot of money on marketing and branding their product as higher-end. This may not mean better quality, but it can make a higher price tag.
Definition- Memory foam density refers to the weight of the foam given its volume. In other words, how much does one cubic foot of the foam weigh.
Heat issue- As noted above, some memory foam mattresses tend to sleep hot and can provide for an uncomfortable sleeping experience. In general, higher density foams have a greater risk of sleeping hot.
Cost- Generally, higher density foams cost more. The main reason for this is that the raw materials used to make the foam are more costly. Over time, in the industry higher density has also come to be interpreted as higher quality (although higher density by no means indicates/guarantees a preferable mattress).
Motion Isolation- With high-density foams, the rest of the mattress does not give in when you lie down on it. With low-density foams, this is often not the case. As such, high-density foams are better with motion isolation. This means that if you sleep with a partner, you will most likely be less disturbed by the movements of your partner with a higher-density foam mattress.
Support- Generally, higher-density memory foam has better support than lower-density memory foam. This isn’t always the case, but it is a good general rule to follow.
Rebounding- Light-density foams rebound more quickly than high-density foams. As a result, some people feel a little more discomfort if they tend to move a lot while in their bed with a high-density foam.
Feel/Sleep Positions– Higher density foams have the “sleeping on a cloud”-like feel that you hear about. Some people enjoy the feeling of sleeping “in the mattress.” That is generally the feeling that higher density foams provide. This is because you sink into the mattress, but the surrounding foam doesn’t give in. With softer densities, the foam surrounding you gives in, in addition to the foam you have direct contact with. For this reason, higher density foams are better at contouring specifically to your body because the rest of the mattress does not give in to pressure. This makes higher density foam ideal for back sleepers. Stomach sleepers probably want lower density foams because they are softer. Side sleepers generally want a medium-density foam that is soft enough to relieve pressure points but also allows for optimal contouring and support. These are general rules but the proper mattress depends on each unique individual.
When it comes to thickness in memory foam mattresses, there are a few things you should note. First, you should know the total thickness of the mattress. The mattress will consist of memory foam on top, but there will also be a base layer of more standard foam. After you know the total thickness of the mattress, you should know what portion of the thickness is memory foam and what portion is the base layer standard foam.
It’s a general rule that the higher the total thickness, the more expensive the mattress will be. Also, the greater percentage of memory foam that the mattress contains, the more expensive the mattress will be. That is because the thicker mattresses are more expensive to manufacture and the value the customer gets is higher. More memory foam thickness generally means more comfort and contouring support. People that are heavier should seek a mattress with higher thickness to make sure they can have enough cushion to support their body weight. It’s impossible to say what the right thickness should be, because it depends on personal preference and there are many other factors that can affect the sleeping experience, such as the density and the materials used in construction.
It’s difficult to say how long an average memory foam mattress will last. That is because it really depends on the specific mattress in question and how it’s constructed. The thickness, density, and construction process all play a part in how long the mattress will last. Generally, more dense mattresses will last a longer time. The extra density allows the mattress to keep its shape and prevent against general wear over time. However, because there are several factors that go into the longevity of a mattress, I would suggest reading a number of reviews for each individual mattress that you are considering. You’ll be able to get a pretty good sense of how long you can expect the mattress to last by doing so.
Body Type Discussion
There are a lot of factors that go into which mattresses are best for certain sleeping positions. Having said that, I will try to give my thoughts on each sleeping position as they related to memory foam mattresses.
Stomach Sleepers- As a stomach sleeper, memory foam can be great because it will allow you to breathe more easily. You should generally look to find a mattress with a lower to medium density, as that type of mattress will be softer. If the density is too low, however, your back may arch too much, which can lead to potential back pain.
Side Sleepers- As a side sleeper, memory foam will be very effective at relieving the pressure points of your hips and shoulders. However, you also want to make sure the mattress is supportive so you don’t develop an unnatural posture that can lead to back pain. Generally, a medium-density memory foam is ideal for this type of sleeper.
Back Sleepers- As a back sleeper, the pressure on your body is more evenly distributed than when you sleep on your side or stomach. A mattress that is too soft will cause your back to form unnatural posture. At the same time, a mattress that is too firm will put too much pressure on your lower back. As a result, a medium-firm mattress is generally ideal for back sleepers. A medium-density memory foam mattress will serve back sleepers well.
Relieving Pressure Points- The main benefit of memory foam vs another type of mattress is the ability to relieve pressure points. Consider side sleepers, who choose a sleeping position that naturally puts significant pressure on their hips and shoulders. Memory foam gives in and allows the hips and shoulders to sink down into the foam, relieving the pressure. This ability to relieve pressure points is the main reason why memory foam became so popular starting in the 1990’s.
Motion Isolation- Another big advantage memory foam mattresses have over innerspring ones is in motion isolation. This is especially important if you sleep with a partner. With high-quality memory foam, pressure on one side of the bed is not felt on the other side of the bed. So, if your partner moves around on his/her side of the bed, you won’t necessarily feel anything on your side of the bed.
Other- There are a few other main benefits that memory foam mattresses. They are much quieter than innerspring mattresses. The ability to contour to one’s body makes these mattresses ideal for heavier people. Also, generally memory foam mattresses are great for anyone with pain on certain parts of their body.
Getting Hot Issue
One common complaint with memory foam mattresses is that they sleep hot. Generally, a cool environment is ideal for sleep, so sleeping hot can often get in the way of a good night’s sleep. The chemical composition of the polyurethane (what memory foam is made of) tends to trap heat and impede air circulation. As a result, depending on the construction of the memory foam, a percentage of owners of this type of mattress report discomfort from sleeping hot. Not all memory foam is created equal, however, and mattress companies have tried a number of ways to combat this issue. Please note the following:
Gel-infused: A lot of companies will infuse a cooling gel into the memory foam in order to alleviate the heat concerns. The gel will feel cool to the touch and take on the temperature of the room. However, many owners and several studies show that gel-infused memory foam has only a very small effect on the “sleeping hot” effect. In fact, I spoke with one industry insider who claimed a gel-infused memory foam would only decrease heat by less than ⅓ of one degree.
Gel layer: Rather than having gel infused throughout the mattress, some companies will have an entire gel layer in the mattress. This construction has been shown to be effective in trapping heat and providing a cooler sleeping surface, as it allows the mattress to take better advantage of the cooling properties of the gel. The downside is usually this type of mattress will be more expensive.
Plant-based: Some companies replace some of the oil-based foam components with bio-based oils. This is a more eco-friendly approach, but in most cases it can mean the mattress will sleep less hot. The bio-based components tend to be more breathable, allowing for better air circulation and heat dissipation. As a result, plant-based memory foam does a good job of eliminating the “sleeping hot” issue. The trade-off is that this solution almost always means greater cost, so you would have to be willing to pay extra for a mattress constructed in this way..
The Effect of Density: As I mentioned above, the composition of memory foam tends to impede air circulation. It therefore makes sense that the density of the memory foam has an impact on heat retention. As almost all sources agree, the higher density of the foam, the greater the chance that it will sleep hot. Higher foam density does provide better support and longevity, but it comes with the added risk of “sleeping hot.” Companies who have higher foam density models need to take extra care to address this issue as a result.
A lot of people complain about a chemical odor emanating from memory foam mattresses when they first receive them. A lot of people in the industry refer to this as “off-gassing.” This can especially be the case if the mattress is vacuum-packed. However, this smell generally goes away within the first 2-3 days of receiving the mattress. You can diminish this effect by opening up a window in the room the mattress is in or otherwise placing the mattress in a well-ventilated room. There is no evidence that this is harmful at all to humans, so it is really more of a temporary annoyance. With any quality manufacturer, the smell will dissipate quickly and will not be an issue going forward.
Another common complaint for memory foam mattresses is that the mattress becomes softer over time. This increasing softness can make the mattress less supportive and less ideal. Softening depends on several factors, such as the density, thickness, and materials used in construction of the mattress. Complaints about softening vary widely among different memory foam brands. I would therefore suggest reading a number of individual reviews for the brands you are looking at to see what the frequency of softening complaints are. In general, higher-density memory foams tend to hold up better over time and face fewer softening complaints as a result.
Sagging is a complaint that occurs with any type of mattress. Over time, a mattress can develop a crater from the pressure applied to it from your body over time. This creates a less-than-ideal sleeping environment with less comfort and support. Studies show that memory foam mattresses are no worse when it comes to sagging than other types of mattresses. Complaints about sagging also vary widely within the memory foam category depending on the quality of materials used in construction, the thickness of the mattress, and the density of the foam. While memory foam mattresses generally do well in this category, I would advise you to read reviews of the individual mattresses you are taking a look at to make sure there are not a disproportional number of sagging complaints.
Memory foam mattresses should not be confused with mattresses that have a memory foam topper. Any type of mattress can have a mattress topper added to it. Innerspring mattresses, for example, can certainly have a memory foam topper added to them. In general, people will add a topper when they feel that their mattress is a little too firm. The topper will create a softer sleeping environment. This solution is often much more convenient than replacing an entire mattress. It should be noted that toppers generally do not last as long as a normal mattress. They can, however, be a great solution if you simply want to make your mattress a little bit softer and you don’t need a really long-term fix.
More mattress types and brands are reviewed on our mattress reviews page.