Is sleeping on a soft mattress good for you? Or is it causing your back pain?

Soft mattresses can be wonderful for some sleep styles, but it’s important to know who will benefit and who won’t

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Mattresses come in a range of firmness levels: from soft through medium-soft and medium, to medium-firm and firm. And whilst a soft and cushioning mattress might sound appealing on paper, is it actually good for you to sleep on a soft mattress? 

As with many things in the sleep world, there’s no ‘one answer fits all’ to this question. For some people, a soft mattress could be the answer to all their sleep problems, while for others it will just cause more issues. In this guide we’ll help you decide if a soft mattress is right for you and your sleeping style.

Remember as well that most of the best mattresses on the market come with generous trial periods, which means you can try out a soft mattress and return or exchange it if it isn’t right for you.

Is a soft mattress a good choice for your sleeping style?

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Soft mattresses can work wonders for some sleepers. We’ll round up who a soft mattress could suit but do remember that personal preference plays a part in choosing a mattress as well. If you love a particular firmness and have always slept well on it, then there is a strong argument for not fixing something that isn’t broken.

Side sleepers – 'Soft mattresses can be beneficial for side sleepers as they allow the body to sink into the mattress, aligning the spine and relieving pressure points on the shoulders and hips,' explains sleep expert, Dr. Chester Wu,. A soft mattress will cushion your body, whereas a firmer one might exert too much pressure and leave you in discomfort. If you’re looking for the ideal mattress for side sleeping, check out our guide to the best mattresses for side sleepers.

The memory foam ‘hug’ – Soft mattresses generally contain memory foam, which gives the softer, sink-in feeling that allows the mattress to contour to your body. This distinctive ‘hug’ tends to provoke a real love it or hate it reaction but, if you do enjoy this sensation, a soft, memory foam mattress is one to consider.

Joint pain – Softer mattresses allow you to sink into a mattress, which in turn reduces pressure on shoulders and hips. As Dr Wu says, 'A softer mattress can help alleviate joint pain and discomfort from conditions like arthritis by providing more cushioning.' And, as we’ve explained above, aches and pains can be particularly reduced for side sleepers on softer mattresses.

Lightweight sleepers – 'Heavier bodies need a bed that is more supportive. People with less body weight might prefer a softer mattress because they don't weigh enough to compress a firm mattress, which can lead to pressure points and discomfort.' explains Dr Wu. If you weigh less than the average person you might find that a firmer mattress just doesn’t offer enough pressure relief – conversely, if you weigh more than average, you’ll need more support than a soft mattress can provide.

Dr Chester Wu
Dr Chester Wu

Dr Chester Wu is double board certified in Psychiatry and Sleep Medicine. In addition to his work as Rise Science’s Medical Reviewer, Dr. Wu provides sleep medicine services, medication management, and psychotherapy to adults at his private sleep medicine and psychiatry practice in Houston.

Is sleeping on a soft mattress bad for you?

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For some sleeping positions a soft mattress is not a good choice. A soft mattress can cause more harm than good for some sleepers and sleeping styles. Let’s run through some of those now.

Back and stomach sleepers – 'Back sleepers generally need a firmer mattress to keep their spine properly aligned', says Dr Wu. 'A soft mattress might cause the hips to sink into the mattress, leading to an unnatural curvature of the spine and potential back pain.' The same is true for stomach sleepers, who need a firm mattress to keep their hips lifted and their spines aligned when they’re lying on their fronts. 

Back pain – As a general rule of thumb, the best mattresses for back pain tend to be firmer than a soft mattress. Dr Wu explains that, 'If you have chronic back pain, a soft mattress might not provide the necessary support, potentially exacerbating the pain.' This is because a soft mattress doesn’t provide enough spinal support under the back, which can lead to pain. 

Hot sleepers – 'If you sleep hot, you may want to opt for a firmer mattress,' says Dr Wu. 'Soft mattresses, particularly those made of memory foam, can retain heat, which might lead to discomfort for people who tend to sleep hot.' The ‘hug’ of softer mattresses can also make it harder to stay cool, with less of the sleeper’s body exposed to the air. If you do sleep particularly hot, we’d recommend investing in one of the best cooling mattresses that use specialty materials to help keep you cool at night. 

Which is the best soft mattress?


What is the best mattress firmness?

The word 'best' is tricky when it comes to mattresses, it really comes down to personal preference. Follow the advice above to start to work out what's going to be the best firmness for you and then either go into store and test out some different mattress firmness or make a call based on what you think will work best for you and order a  mattress online from a company that offers a generous policy on a sleep trial so you test it out at home. Generally, we would say a medium-medium firm mattress is the standard and most would find that comfortable so would be a good place to start if you are unsure. 

What’s the most common mattress firmness?

If a company only makes one mattress, you’ll generally find that they rate the mattress firmness medium-firm. This is a happy middle ground that suits a large number of sleepers and produces a mattress that isn’t too soft or too firm. 

Sleep expert, Dr. Chester Wu, explains, 'From a medical point of view, the ideal mattress is one that is firm enough to support the spine but soft enough to be comfortable. A bed that is too soft can cause the spine to sag, which can lead to pain and other problems. A bed that is too firm can also be uncomfortable and can make it difficult to get a good night's sleep'.

So the takeaway, as with so many questions when it comes to mattresses, is whether a soft mattress is bad for you totally depends on the individual. How you sleep, what position you sleep in, and whether you have any aches or pains. We would always advise you to test out your future mattress either in-store or by making the most of sleep trials so you can work out what's going to be best for you. 

Jo Plumridge

Jo Plumridge is a freelance writer and photographer with over 20 years of experience writing for a variety of magazines, websites and books. She writes, perhaps unsurprisingly, about photography, but also on all things interior design and sleep-related, alongside reviews of home and tech products. Jo loves exploring the latest design trends, although she’s yet to find a carpet that doesn’t show up the cat hair from the cats she and her husband foster.