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Mattresses Don't Last Forever. Top Signs You Need a New One

The typical life span of a mattress is seven to 10 years. During that time, your mattress is collecting things like dust mites and skin cells at night.

Taylor Leamey Senior Writer
Taylor Leamey writes about all things wellness, specializing in mental health, sleep and nutrition coverage. She has invested hundreds of hours into studying and researching sleep and holds a Certified Sleep Science Coach certification from the Spencer Institute. Not to mention the years she spent studying mental health fundamentals while earning her bachelor's degrees in both Psychology and Sociology. She is also a Certified Stress Management Coach.
Expertise Bachelor of Science, Psychology and Sociology Credentials
  • Certified Sleep Science Coach, Certified Stress Management Coach
Taylor Leamey
5 min read
Man and woman talking while they are moving a new mattress into a bedroom

It may be time to get a new mattress.

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Here's a quick, gross mattress fact: Mattresses gain a small amount of weight over time, and it isn't from the foam expanding. Your mattress absorbs dead skin, dust, skin oils and moisture. And then there are the dust mites that are lurking inside your mattress.

Your mattress isn't going to last forever. Not only is it collecting debris, but it will also start to sag or groan as time goes on. The older your mattress gets, the less it will give you what you need. Let's talk about what's inside your mattress and when it's time to get a new one. 

For more, here's how to best wash your mattress cover and tips to make your mattress last longer.

This is what's inside your old mattress

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Body fluids

Your mattress is kind of like a sponge: When something comes in contact with it, the mattress will absorb it. All the sweat, blood, saliva and other body fluids that touch your mattress leave traces that collect over time. Fluids and moisture in your mattress give way to fungus and bacteria. 

Amerisleep conducted a study that investigated bacteria levels in mattresses of varying ages -- less than a year old, two years old, five years old and seven years old. Results showed that all mattresses tested positive for bacteria. However, only the seven-year-old mattress swabs tested positive for bacilli bacteria. Most rod-shaped bacteria fall under the bacteria class of bacilli. Some bacteria under this category can be harmful, like bacillus cereus, which can cause illnesses like vomiting and diarrhea. Other bacteria in the class bacillus can cause urinary tract infections, sinus infections and pneumonia

Dead skin cells

You lose millions of skin cells every hour. That continues when you sleep and roll around on your mattress. The skin cells don't rest on top of the bed; they make their way into the mattress. The accumulation of skin cells isn't inherently a problem. However, they are the main food source for... 

Dust mites

Gross: Dust mites and mite feces are living in most people's mattresses. An estimated 4 out of 5 American homes have dust mites. Dust mites are different from bed bugs. They're microscopic bugs that aren't visible to the naked eye. They live by eating the dead skin cells collected in the mattress and thrive thanks to the humidity our bodies produce at night. Essentially, mattresses are dust mite heaven -- there is no place they would rather be. 

The good news is that dust mites don't bite and typically don't impact you... unless you're allergic to them. Dust mite allergies are common: Around 20 million people are estimated to be allergic to dust mites. Allergy symptoms of dust mites include a runny nose, watery eyes, sore throat or asthma symptoms. 

If you're not ready to replace your mattress, you can take steps to get control of dust mites.

  • Wash your bedding weekly. 
  • Dust and vacuum your bedroom if you have carpet. 
  • Invest in dust-mite-proof mattress and pillow covers. 
  • Invest in a dehumidifier for your bedroom. Dust mites need humid air to survive. 
Person using the upholstery attachment on their vacuum to clean their mattress

Regularly cleaning your mattress can help it last longer.

Andrii Borodai/Getty images

How to clean your mattress

Cleaning your bed can help keep dead skin cells and dust mites from building up. It's something you should do roughly twice a year. 

Use your vacuum cleaner's wand or upholstery attachment and do an initial pass-through that collects all the things on the surface. Make sure you pay close attention to all the creases and seams. Next, you can move on to any stains and sweat build-up. Spray your mattress with a combination of warm water and dish soap -- roughly a ratio of 1 teaspoon of liquid dish soap to 1 cup of warm water. After you let the solution sit for a few minutes, scrub your mattress with a damp towel. Finally, you want to sprinkle baking soda across the mattress to help absorb moisture and neutralize odors. Leave the baking soda for at least an hour and vacuum the mattress thoroughly. 

Once you've cleaned your mattress, it's a good idea to add a fabric waterproof mattress cover that protects from dust mites. This will make cleaning your mattress easier in the future. Cleaning your old mattress after years of use won't resolve the accumulation of skin cells and dust mites. It will help, but cleaning your mattress is something you want to do throughout the lifetime of your bed. 

When is it time to get a new mattress? 

Mattresses have a shelf life. While the differing materials influence how long a bed will last, they typically have a lifespan of about eight years. Most people don't run off to buy a new mattress the second they hit eight years, though, because mattresses are expensive. And the truth is you might not need to buy one yet. How quickly your mattress wears out depends on how often it's used, your body type and how well you take care of it. 

A young family sitting on a bed while shopping for new bed in a mattress store

If your mattress is no longer comfy, it's time for a new one.

Valerii Apetroaiei/Getty Images

However, sleeping on an old mattress can significantly affect your sleep quality and overall health. Use these common signs to determine if you should invest in a new mattress:

  • You wake up sore and in pain.
  • No matter how much you sleep, you never feel rested. This can result from waking up throughout the night because you can't get comfortable. 
  • You have allergy flare-ups because of your old mattress. 
  • Your mattress squeaks when you move around on it. 
  • Your mattress is sagging around the edges or in the middle. 
  • There are lumps or imprints from your body on the mattress. 

Understandably, buying a new mattress can be pretty overwhelming. There are a lot of mattresses to choose from, all of which vary in price, material and feel. But it isn't hopeless. When looking for your next mattress, ask a few important questions. Or how much money do you want to spend? Determining important factors like your body type and firmness preference can easily help you narrow down your options until you find your dream bed. 

Too long; didn't read?

Mattresses don't last forever. In addition to possibly keeping you up at night, your mattress may be triggering allergies or impacting your overall health. The average mattress is filled with body fluids, dead skin cells and millions of dust mites. And don't forget about the potential fungus and bacteria multiplying beneath the surface. Once you're approaching around a decade with your mattress, it's time to replace it. 

For more tips, check out these tricks to help you fall asleep at night and six habits to practice for better sleep.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.