Camper in tent sleeping on a foam mattress

Helpful mattress articles

Why I don't recommend a foam mattress

If you’ve ever slept on a foam mattress on a long camping trip, you probably won’t want to sleep on one again. 

Now, I’m not saying that no one should ever buy a foam mattress. I’m also not saying that you can manufacture a really good mattress without foam, as you need the comfort that only foam can bring in the top layers of a mattress. I’m saying that for most of us, only a good quality innerspring mattress will support you properly and enable you to sleep your best. Here’s why:


If I told you to stand up and assume a pose which models good posture, you would probably know what to do – stand tall with your shoulders back and your core switched on. You probably also understand the need for an orthopaedically correct posture when we are sitting or standing. What you may not realise is that we still need to keep our spine in that good posture when we are lying down and we rely 100% on our mattress to do that.

If we sleep on something that just sinks wherever we are heaviest (usually around our middle), we are going to get some aches and pains – usually a sore lower back. When the spine is out of alignment it can also lead to headaches, pain in joints, a weaker immune system and poor sleep.

Mattress innerspring units have the unique ability to push up and support the body continuously along it’s length, helping to keep your spine in it’s correct alignment. Newton’s third law states that for every force, there is an equal and opposite force. This is true for springs, which store and use mechanical energy to achieve this. Foam, on the other hand, doesn’t “push up” it only sinks.

A foam mattress might feel quite comfortable to some people when they first sleep on it. Unfortunately, the problems of sleeping in poor spinal alignment can take a while to show themselves.

Heat retention

A solid foam mattress will feel unbearably hot for a lot of sleepers. Foam is made up of billions of open, hexagonal cells with rubber-like walls that capture and hold a sleeper’s body heat. Whilst you need foam for the comfort layer in a mattress, having an open, innerspring system underneath the foam will help to disperse that body heat and will also allow for a greater amount of airflow through the mattress.

A quick read through online reviews about foam mattress-in-a-box brands (we mean on an independent forum, not the reviews on the product website) will reveal quite a few people who find the mattresses unbearably hot.


Let’s just say that you took apart a 50-year-old mattress (ewww!) you would probably find that the fabric was brittle and splitting and underneath this, the foams used in the comfort layers of that mattress would have disintegrated into hard clumps or handfuls of dust.  What you might be surprised to find is that the innerspring system would be fully intact and still performing well. In any mattress, it is the foam that gives out well before the spring system. Foam is made up of billions of multi-dimensional cells that are held open with rubbery “walls” around each cell. As foam ages, the walls break and the individual cells collapse, meaning that the foam loses it’s bouncy, cushioning qualities. In cheaper foams, these cells start to break down from the moment that you start sleeping on the bed. In a rolled foam mattress-in-a-box, you might notice the change within the first year. In the second year, you might just find that the mattress has lost its comfort entirely.

In a good innerspring mattress, the spring system can still provide a good amount of comfort even after the foam has lost all of it’s cushioning. I quite often hear people tell stories of a 20 year old* mattress that is still comfortable. On the other hand, I have never heard of a foam mattress that lasts even a fraction of that time.

*We would never recommend that you sleep on a 20 year old mattress, mainly because of the trillions of dust mites that are probably living in it. You might want to read our article “What’s living in that hand-me-down mattress”.