Experts are warning you to change your mattress immediately after a very grim discovery. They said we're meant to be swap out our old mattress for a new one every six to eight years.
Sleeping on an old one puts us at risk of inhaling gross bacteria such as E coli and mould, the experts warned. The results of this can be pretty grim, causing sore throats, itchy eyes, diarrhoea and vomiting.
It can even cause more serious infections as well as pneumonia. And it's not just your immune system that could take a beating. A well-worn mattress can cause back aches and pains, as well as a whole string of sleep problems.
Sleep specialists at Opera Beds said: "Mattresses provide the foundation and support necessary to achieve good quality sleep. "The right mattress can elevate and influence your sleep by providing pressure relief and preventing you from waking up with aches and pain in the morning.
"Finding a suitable one that caters to your sleep style and requirements is essential for overall comfort, ensuring proper physical restoration, cognitive function, emotional well-being, and overall vitality.
"It’s a personal choice and one that should take individual needs, preferences, and any underlying health concerns into consideration. But once we've got one, many of us fail to recognise the tell-tale signs that it’s time to be replaced.
"Depending on factors like usage and wear and tear, mattresses should ideally be replaced every six to eight years."
Here's everything that could be hiding in your mattress, and the problems it can cause.
Bacteria
There's all sorts hiding in your old mattress. Research shows they're hotbeds of microscopic activity - with staphylococcus, lactobacillus, streptococcus and E coli all found.
These can cause nasty skin infections and upset stomachs, as well as abscesses, joint problems and even pneumonia. Urinary tract infections (UTIs) and heart, bone and eye infections are also possible.
Bodily fluids
From sweat and saliva to semen and skin oils, your bed is full of it. The liquids seep through your sheets and are absorbed by your mattress, sticking around for years. Experts reckon that over the lifespan of your mattress, these fluids could fill two bathtubs to the brim.
It is estimated the average adult sweats 26 gallons a year in bed, making it a warm, moist home for fungus. Yeast, mould and bacteria like staphylococcus aureus can make its way into the crevices, leaving you at risk of painful red lumps on the skin, sores, crusts and blisters, and painful eyes and eyelids.
Mould spores
If that wasn't enough, mattresses can become susceptible to mould spores. "These can be detrimental for health in the short and long-term," Opera Beds said.
"This can be particularly bad if a bedroom gets damp or isn't ventilated properly. Some of the first signs of mould exposure can be the sniffles, sneezing, and red or itchy eyes or skin."
The most commonly found spores are penicillium, cladosporium, alternaria, and aspergillus, which can cause allergy symptoms like a runny nose, sneezing, congestion and itching.
Dust mites
Dust mites can also burrow in the fibres, causing or worsening skin problems like eczema and respiratory issues like asthma. "The reality is - the older your mattress, the more dust it will have gathered," experts said.
The critters feed on flakes of dead skin - which your mattress is full of. In eight years, we shed an average of 11lb (5kg) of dead skin cells - so double that if you're sharing with a partner or pet.
Sleep
Away from the germs, an old mattress can wreak havoc on your sleep.
You may find yourself waking up more often, experiencing discomfort or struggling to nod off.
"A lack of sleep affects our day-to-day lives and our ability to function properly, and the issue will cause a negative cycle of sleep disruption, meaning you associate sleep and bed with frustration, causing further problems," Opera Beds said.
Aches and pains
And finally, saggy springs and floppy foam can cause a range of aches and pains.
OperaBeds said: "A tired, worn out mattress likely won't be providing your body with the foundation it needs for a restful sleep, and you might find yourself waking up with pains, without realising why, and thinking it's due to your sleeping positions.
"A lot of older mattresses develop dips in them, which is bad for support and posture."
