How often you should buy a new mattress (plus President's Day deals on mattresses)

If you've been having a hard time falling asleep, your mattress might be the cause.

Your mattress is not meant to last forever. So if you've been sleeping on the same mattress for a number of years, chances are your mattress probably isn't as comfortable as it used to be. Mattresses can be damaged a number of ways: the sleeping indentations of people and pets can cause heat-trapping lumps and bumps and sagging. Mold can be caused by humidifiers, ceiling leaks, sitting on your mattress in a wet towel or even heavily sweating in your sleep.

If an old, lumpy, sagging and potentially moldy mattress isn't allowing you to sleep comfortably, you're likely not getting the benefits of a good night's sleep. Sleep is important for vital functions such as neural development, learning, memory, emotional regulation, cardiovascular and metabolic function, and cellular toxin removal.

So when should you buy a new mattress?

When to buy a new mattress

According to the American Sleep Association, you should replace your mattress every 8 to 10 уеаrѕ.

To extend the life of your mattress, use a washable mattress protector. A protector can keep your mattress clean and dry, prevent mold, and resist dust mites. The ASA further advises rotating your mattress 180 degrees at least once every 90 days, for more even wear. If you have a double-sided mattress, you should also flip it. Double-sided mattresses are designed to be used on both sides.

Of course, if the mattress you own just isn't feeling comfortable anymore, now's a great time to replace it regardless of when you bought it.

Shop President's Day mattress deals

The best mattress deals have hit the internet for President's Day weekend. Shop these CBS Essentials mattress picks and save hundreds of dollars on a brand new bedroom essential.

Essentia Stratami full mattress: $2,472

The Stratami mattress, currently 20% off during Essentia's President's Day sale, is one of the brand's best sellers. It's made with sustainable and ethical farming practices. The mattress is vegan, made with certified-organic latex and is impervious to dust mites, making it an ideal choice for allergy sufferers. It can be ordered in a twin, twin XL, full, queen and king.

Essentia Stratami full mattress, $2,472 (regularly $3,090)

$2,472 at Essentia

Casper Wave hybrid queen mattress: $2,460

Casper is offering up to 15% off its mattresses until February 22. And Casper's President's Day sale includes 10% off of everything else, in case you need some new bedding as well.

This Casper Wave hybrid mattress is highly rated by customers. It's outfitted with gel pods that lift your waist and lower your back for better alignment. The mattress is made with Casper's AirScape 3 + cooling gel technology, which helps prevent the mattress from becoming hot.

Casper Wave hybrid queen mattress, $2,460 (regularly $2,895)

$2,460 at Casper

If you tend to sweat while you sleep, the Casper Wave hybrid can also be purchased with Casper's Snow Technology. The brand's advanced cooling feature is made with a layer of cooling gel that helps prevent overheating for up to 12 hours.

Casper Wave hybrid queen mattress plus Snow Technology, $2,885 (regularly $3,395)

$2,885 at Casper

Casper also offers a supportive foam pillow with the same cooling Snow Technology. You can save 10% on it now.

Casper foam pillow with Snow Technology, $126 after 10% discount (regularly $139)

$139 at Casper

Birch Luxe Natural by Helix queen mattress: $2,499

Birch is an offshoot of popular mattress brand Helix, offering comfortable and luxurious beds, responsibility sourced and sustainably produced, handcrafted and assembled in the USA. The mattresses are also Greenguard Gold certified and GOTS certified organic. They offer two options, including the upgraded Birch Luxe Natural (shown here), made with materials such as organic cashmere, organic New Zealand wool, Fairtrade cotton and Pulse latex. This medium-firm hybrid limits motion transfer with the help of 1,000 individually wrapped steel coils and natural latex to cradle the body and relieve pressure points.

Use the code PRESDAY400 to save $400 on this mattress and receive two free pillows at checkout.

Birch Luxe Natural by Helix queen mattress, $2,499 (reduced from $2,899)

$2,499 at Birch

Saatva Classic queen mattress: $1,495

Saatva Classic is a popular hybrid mattress. It can be ordered in two heights and various levels of firmness, ranging from plush soft to firm. It offers two layers of coils and a pillow top filled with pressure-relieving memory foam. Saatva also provides a generous, risk-free trial period of 180 nights.

Saatva's President's Day sale includes $200 off a purchase of $1,000 to $1,999 until February 21.

Saatva Classic queen mattress, $1,495 (regularly $1,695)

$1,495 at Saatva

During Saatva's President's Day sale, save $450 on a purchase of $4,000 or more. This Solaire adjustable mattress in a split California king offers 50 firmness settings on both sides and claims to have virtually no motion transfer.

Saatva Solaire adjustable California king mattress, $4,145 (regularly $4,595)

$4,145 at Saatva

Purple queen mattress: $1,274

Purple mattress is having a President's Day sale as well. The base-level Purple mattress is $125 off, the Hybrid mattress is $200 off and the Hybrid Premier is up to $300 off. The brand is also offering up to $200 off bedding bundles.

Technically foam models, Purple mattresses feature the company's Purple Grid technology, which layers hyper-elastic polymer between tiers of foam or coils, depending on the model. The traditional Purple mattress features two levels of the brand's trademark gel, paired with dual-layer foam, while the Purple Plus boasts two extra layers of comfort foam. The Purple Hybrid adds pocked coils for more airflow and durability, and the Purple Hybrid Premiere 3 or 4 -- the luxury models -- offer three or four inches of the buoyant-feeling gel. Every mattress comes with a 100-night, risk-free sleep trial period.

Purple queen mattress, $1,274 (regularly $1,399)

$1,274 at Purple

Purple Hybrid queen mattress, $2,199 (regularly $2,399)

$2,199 at Purple

Purple Hybrid Premiere queen mattress, $2,749 (regularly $2,999)

$2,749 at Purple

Avocado Green queen mattress

Avocado Green mattresses are 10% off for President's Day, now through February 28. Avocado offers a number of environmentally friendly mattresses, including the Avocado Vegan, a PETA-approved, no-wool hybrid. All the company's mattresses are constructed from non-toxic, natural and organic materials. The Avocado Green Mattress is made with 100% organic latex, 100% organic wool and 100% organic cotton -- and no polyester, polyurethane or toxic fire retardants.

Avocado also offers one of the most generous trial periods: one year.

Avocado Green queen mattress, $1,439 (regularly $1,599)

$1,439 at Avocado

Brooklyn Custom queen mattress: $1,312

Brooklyn Bedding recently unveiled a completely customizable mattress. Available in three sizes -- queen, king and California king -- options include firmness (soft, medium or firm), comfort (gel-infused with deep compression support; an all-natural responsive and breathable latex; or a contouring TitanFlex with pressure-point relief) and top fabric (organic cotton, luxury cooling or recovery).

Everything from Brooklyn Custom is 25% off during the brand's President's Day deals until February 21.

Brooklyn Custom queen mattress, $1,312 (reduced from $1,749)

More mattress deals available now

Nod by Tuft and Needle queen mattress: $450

This inexpensive memory foam mattress by Tuft and Needle is made with two layers of open-cell foam. The first layer provides cushiony comfort while the second layer provides support. The mattress is available in sizes ranging from twin to California king.

Nod by Tuft and Needle queen mattress, $450 (regularly $500)

$450 at Amazon

Novilla queen mattress: $335

This four-layer foam mattress features a gel top layer to keep you cool and an egg crate foam layer to increase airflow and prevent your mattress from feeling hot. The multiple foam layers are meant to distribute pressure and mold to your body ensuring a comfortable sleep. The mattress is available in sizes ranging from twin to California king.

Novilla queen mattress, $335 (regularly $380)

$335 at Amazon

Sweetnight full mattress in a box: $392

Sweetnight says this mattress resists sagging. Its constructed with individually wrapped innersprings and features gel memory foam for support and pressure relief. The medium-firm feeling mattress is available in full, queen and king sizes.

Sweetnight full mattress in a box, $392 (regularly $503)

$392 at Amazon

Serta 7" cooling gel memory foam queen mattress: $349

Amazon has a Serta mattress on sale. This cooling gel foam mattress uses compression technology to pack the mattress into Serta's smallest carton yet, making it an ideal choice for people who live alone and might have trouble transporting a mattress from the front door to the bedroom.

Serta 7" cooling gel memory foam queen mattress, $349 (regularly $399)

$349 at Amazon

Zinus 12" green tea cooling gel memory foam queen mattress: $284

This Zinus mattress is infused with green tea for what Zinus calls its "most cooling formula yet." The thick memory foam mattress includes a 10 year warranty.

Zinus 12" green tea cooling gel memory foam queen mattress, $284 (regularly $350)

$284 at Amazon