It can be tricky keeping a mattress as fresh as the day you bought it, and despite your best efforts, your mattress may start to stain. If you're wondering ‘why is my mattress turning yellow?’ you're not alone. But rest assured, there are things you can do to freshen it up and prevent the yellowing from becoming worse.
Here, we go through some of the main reasons why a mattress might turn yellow. We also look at the health implications of a yellow mattress, and most importantly, how to prevent it from happening in the first place.
If your mattress needs cleaning then our feature on how to clean a mattress offers plenty of valuable advice. Once you’ve got it spruced up, we also share some easy solutions to keep it that way for longer.
And if all this is too late and you need a new mattress, take a look at our best mattress guide. It's packed with top options for all budgets, and the advice here will help you keep it clean and looking good for years to come.
Why do mattresses turn yellow?
The thought of sleeping on a yellow mattress is never pleasant, but sometimes a mattress turning yellow isn’t as gross as it sounds. In fact, most of the time, a yellowing mattress is caused by oxidation as the mattress naturally ages. When this happens to a mattress, it's perfectly safe to sleep on.
However, if you’ve had your mattress for some years, then it could be time to replace it anyway. Check out our guides to the best mattress in a box and the best memory foam mattress to see what’s on offer.
Aside from an ageing mattress, there are other reasons why a mattress might turn yellow. And some of these can be harmful to your health, providing a breeding ground for bacteria and other nasties, such as bed mites. The reasons for a stained mattress might be:
- Yellowing due to a build-up of natural body oils and sweat
- Accidents involving urine, vomit, or blood, including from pets
- Mould and dampness setting in
- Spillages from food and drink
- A build-up of body moisturiser or other skincare/hair products
Mattresses have an average lifespan of eight years, but, as we explain in our feature on how long does a mattress last, some have a much longer lifespan. If your yellowing or stained mattress is likely caused by any of the above, then read on to find out more, plus tips on how to clean it up.
Is it safe to sleep on a mattress that’s turning yellow?
If you’re wondering whether it’s safe to sleep on a yellow mattress, the answer is: it depends… As we mentioned earlier, yellowing is something that can happen naturally to a mattress over time, but if your mattress is starting to smell or is stained in patches, then it could be unhealthy to sleep on.
If you're prone to allergies, and notice you're coughing more or itching, rubbing your eyes, or waking in the night, it could be a sign that mould is setting into your mattress. Or, it could mean that dust mites and bugs are feasting on the dead skin cells, sweat, and bacteria in your mattress, and leaving their droppings to trigger your allergies.
To help you keep your mattress hygienic and stain-free, we look at the top five causes of yellowing mattresses, and how to fix them.
1. Mattresses naturally turn yellow with age
The reason mattresses turn yellow over time is because the materials oxidize as they react to the oxygen in the air. This gradual process is natural, harmless and can't be prevented, especially with memory foam. However, keeping the mattress out of direct sunlight and away from excessive moisture will slow down the process.
You should be able to tell if the yellowing is age-related, as it won't have an odour and can't be cleaned up. Most mattresses should be replaced every seven-ten years (some, such as all-latex mattresses, can last a little longer), and yellowing due to age is usually a reliable indicator that it’s time to upgrade.
2. Sweat and body oils can cause yellow mattress stains
If you frequently sleep hot, or overheat occasionally because you are unwell, then it’s likely you'll sweat more. Over time, sweat can accumulate and lead to your mattress staining. Sweat stains won’t show up immediately on your mattress, so frequently washing your bed sheets will help keep things fresher before it’s too late.
Natural body oils (sebum) can also seep through to your mattress, and again, can take a little while to show up. While sweat and sebum are just a fact of life, regularly cleaning sheets, wearing fresh pyjamas, and using a mattress topper can help keep it off your mattress.
If you start to notice an odour coming through the mattress, it’s likely that the sweat and oils have caused bacteria to thrive, providing plenty for bed mites to snack on. Our guide on how to clean a mattress offers tips on how to freshen up your bed, including with household ingredients such as baking soda. This also works for the body moisturisers and bath oils that can build up and seep into your mattress.
3. Urine stains can turn your mattress yellow
When urine seeps into a mattress, it can quickly cause yellow staining and therefore should be cleaned as soon as possible. If the bed-wetting is fairly frequent, then it will soon build up (especially if it's not cleaned immediately) and lead to mold, odors, and bed mites on the mattress.
If the accident has just happened, strip the bed, and wash the sheets in a washing machine. To clean the mattress, first dab as much of the urine off with a cloth or sponge. Then use an enzyme-based cleaner (designed for biological stains) to break down the proteins in the urine and make it easier to lift. You can also use white vinegar and baking soda, as explained in our guide on how to clean a mattress.
Because mattresses aren’t designed to get wet, it’s important not to use too much water when cleaning. Spot cleaning with a solution or cleaner, and then letting it air-dry thoroughly, is the best way.
If you didn't notice that urine had leaked into the mattress, then over time you may start to notice an odor. Once you've located the stain, baking soda can help neutralize the smell. Sprinkle it onto the affected area and let it sink in overnight. You can then vacuum it up the next day.
4. Uncleaned vomit leaves yellow marks
Vomit - from pets or people - on a mattress can leave an unsightly yellow stain. As with urine, it’s important to clean it up quickly, clearing away as much as you can, then tackling any dampness that's seeped through onto the mattress.
Dab the area with a rag or sponge to remove the excess moisture, and try not to rub it, as this could spread bacteria. Spot clean the area with a fresh rag, using an enzyme-based cleaner, or white vinegar and baking soda.
It’s important to note that some mattresses soak up liquid easier than others, so you may have to spend more time blotting the moisture out first. Also, if you're cleaning a particularly absorbent mattress, apply the cleaner to the sponge rather than the mattress.
5. Spilled tea and coffee can cause yellow staining
There’s nothing better than breakfast in bed. Until, that is, you spill your coffee straight onto the mattress. Again, to prevent staining, you should act quickly and blot the liquid after removing the bed sheets. You can then dab the stain with cold water, and sprinkle a generous amount of salt or baking soda on to lift the stain. Rub the salt/baking soda gently and blot it dry, before vacuuming it up. This should work for most food and drink spillages, including wine.
If it’s an older stain, then you will have to go a little tougher and make a solution of one-part laundry detergent, one-part vinegar, and 10 parts water, and lightly spray it onto the stain. Then take an old toothbrush and brush it gently, letting it sit for 10 or 15 minutes. You can then blot the area dry. If the stain persists, repeat the step with the cleaning solution.
How to prevent yellow stains on a mattress
While there’s nothing you can do about a mattress that's turned yellow due to age, you can at least rest assured it’s not harmful to sleep on. But, if you want to keep your mattress healthy and prevent it from yellowing due to spills, accidents, and sweat for instance, then try the following:
- Use a mattress topper or mattress protector. These are removable and washable, and provide a tougher barrier for liquids getting into your mattress. Some are also waterproof, ideal for younger family members who are prone to wetting the bed. See our best mattress protector and best mattress topper guides to find one that suits your needs.
- To prevent sweat and body oils getting too deep into your mattress, set reminders to clean and air the mattress twice a year or so, along with your pillows and duvets too. Also wash bed sheets and pillow cases regularly.
- Act quickly on all accidental spillages to clean up before the liquid seeps into the mattress too much.
- Avoid eating or drinking in bed. While this is fun, it also increases the chances of accidental spillages.
- Avoid letting your pet sleep on the bed. Again, while this might be cosy, urine accidents – and worse – can happen.
One final note – it’s easier to donate or dispose of a mattress that's clean. If your yellow mattress has gone past the point where it can't be cleaned, you may need to buy a new one. However, disposing of the old one might prove to be tricky, as most charities and some junk removal companies won't take a mattress if it's deemed to be unhygienic. Keeping your mattress as clean as you can right up until the last minute will help when it's time to replace it.
If you're ready to find something new but are unsure what size you need, read our easy guide to mattress sizes and bed dimensions.
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Grace is an experienced sleep writer and mattress reviewer who also contributes to our sister site TechRadar, among other Future plc brands. She's a big fan of organic sleep products and has recently invested in a wool mattress topper that she quite happily describes as "life-changing." (Hey, we're serious about our sleep products). When she isn't testing mattresses or writing about sleep, Grace enjoys reading and creative writing, and incorporates meditation and yoga into her wellness routine.