3 Signs Your Mattress Is Too Soft

And how to pick the perfect replacement, according to a spine surgeon.

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Human beings usually spend around a third of their lifetime sleeping. A good night's sleep helps restore and recuperate necessary energy, ensuring optimal performance the following day. There's nothing quite like sinking into bed after a long day. But if you're literally sinking into your bed, your mattress could be too soft—and it might be a time for a new mattress, said Richard Guyer, MD, an orthopedic surgeon and co-founder of the Texas Back Institute.

Your spine has a natural S-curve, said Dr. Guyer, with the lower back curving inward and the upper back curving out: "If you lay down on a very, very soft bed, the curve is not supported, and you lay like you're in a hammock. I call it the banana position." While the banana position feels oh-so-good when you're chillaxing, it's not the way you want to sleep all night, said Dr. Guyer.

Signs Your Mattress Is Too Soft

So, how do you know if your mattress is not firm enough? "It's one of those black box areas that we as consumers don't know much about," said Dr. Guyer. But there are a few telltale signs that you're not getting the support you need:

  1. There's a dent in your mattress in the morning. This indicates your mattress is not adequately supporting you.
  2. You're tired throughout the day because you're not getting quality sleep at night. According to a December 2021 study published in the Journal of Orthopaedics and Traumatology, sleep disturbances are common. A 2016 meta-analysis on sleep quality in the journal Sleep Medicine Reviews found that 15–30% of adults report sleep disorders, such as sleep onset latency (SOL), insufficient duration of sleep, and frequently waking up at night.
  3. You feel soreness in your back in the morning. Your too-soft mattress may not necessarily cause the pain, said Dr. Guyer; but it can certainly make back pain worse. Back soreness isn't just a discomfort; it can ruin your night (and day). The same 2021 study found that low back pain (LBP) has been identified as one of the leading causes of poor sleep quality.

Back pain is so common that eight out of 10 adults in the U.S. will experience either acute or chronic back pain at some point in their lives, according to the National Library of Medicine.

Based on their analysis of dozens of scientific studies, the 2021 study authors concluded that medium-firm mattresses offer more advantages to subjects with non-specific low back pain. On the topic of too-soft mattresses, the authors concluded that with these mattresses, hips and shoulders sink too much into the mattress, leading to (spinal) column misalignment.

In addition, the authors noted that beds with active control improve column alignment and sleep quality. Another sleep-inducing feature was temperature manipulation using a high heat capacity mattress (HHCM), which caused a reduction in temperature in the skin and increased slow sleep waves and sleep continuity.

The authors wrote that this information "enables healthcare professionals to recommend to patients the correct type of mattress to limit or avoid back pain symptoms, thus providing them with benefits in terms of life quality."

How to Buy a Mattress

If any of the above signs of a (too) soft mattress are true for youand you're ready to invest in a better mattress, Dr. Guyer offered these shopping tips:

Buy a Reputable Brand, but Skip the Top of the Line

Mattresses from the priciest brands usually have too much padding, said Dr. Guyer. Many are sold with a "pillow top" that can be so thick it's almost like having no support at all, added Dr. Guyer.

Choose a Firmness Rating of 4

Brands typically grade their mattresses from 1 to 5, with 1 being the softest and 5 being the firmest. Dr. Guyer said that his patients choose a 4, which should be just right.

Memory Foam Is a Good Option

Mattresses made from this cushy polyurethane material aren't for everyone. But if you like the feel, Dr. Guyer recommended memory foam because it contours to your natural anatomy, allowing an impression of your thoracic spine and lower pelvis while also supporting the rest of your back.

Getting a good night's sleep is crucial to everyday health and wellness. If you have difficulty falling or staying asleep, it can affect all aspects of daily life. One of the best choices you can make is sleeping on a mattress that fosters good sleep health and habits.

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