It's a common misconception that you should replace your mattress every 10 years. The Better Sleep Council recommends every 7 years, but that depends on several factors including the type of mattress, your size, the amount of use (and abuse) that it gets, and how well you're taking care of the mattress. Your age is also a factor as people tend to tolerate less pressure as they get older.

Different types of mattresses have different lifespans:

• Innerspring - 8 years (longer if you can flip it)
• Memory Foam - 8-10 years if you rotate it
• Latex Foam - 15 years
• Gel Foam - 10-15 years
• Hybrid (innerspring with foam) - 10 years
• Waterbed - 12-15 years

The manufacturer or seller of your mattress may offer a buy-back or mattress disposal service, so check your warranty.

This is the most important criteria in deciding when to change your mattress. The manufacturer may claim that your mattress will last 10 years, but if you're in year 5 and you wake up with tightness or soreness, it's time to look at a new mattress. The most common areas where people feel tightness or soreness after waking are in the back, hips, and shoulders.

Understand that this is usually a gradual process. Your mattress won't wear out overnight and the tightness and soreness that you have in the morning will slowly and gradually get worse over time. Be sure to take other factors into consideration, such as your exercise routine. If you just started CrossFit and you're waking up sore, it may not be your mattress.

Most people who need to change their mattress find that it takes a few hours after they wake up to start feeling loose again. If you're not sure if your mattress is the culprit, notice how you feel when you wake up after sleeping in a hotel or in a different bed, and not if that mattress is softer or firmer. Or you could take it a step further and do your research and then order a mattress online that offers a risk-free in-home trial.

A question you should ask yourself is, did you buy the correct mattress in the first place? Most people buy a mattress based on price, often lying on a bed to test it in-store. What they don't realize is that everyone requires a different level of firmness. It's not uncommon that people wake up feeling tightness or soreness in their back, hips, and/or shoulders, and they've gotten used to it. So even if your mattress isn't old enough to be replaced, it may not be the best mattress for you.

As a general rule, the higher-quality mattresses will last longer, but every mattress is different. Check your warranty for details before you buy it. Many manufacturers will cover indentations only up to a certain depth.

Take all the covers off your mattress and look at where you sleep to see if it's uneven anywhere. It's a good idea to rotate your mattress occasionally to even out the wear and tear (not to flip it, as most mattresses are designed to only be used one side up). If you're like most people and you don't rotate your mattress, you may have parts of your mattress that sag.

When you lie in bed do you notice that you seem to fall into a certain spot, or that it's hard to get out of that spot? The problem with a sagging mattress is that your spine is out of alignment, and it keeps your muscles from relaxing, which will make you sleep poorly.

Mattress warranties usually cover having an indentation of more than 1" in the mattress.

If you've gained weight, gained a sleeping partner, or now own large pets that sleep in the bed, you're speeding up the timeline for replacing your mattress. The more pressure that your mattress has to support, the more wear and tear will occur. This is why it's recommended that you don't let kids jump on the bed and that you don't stand on your mattress. Standing puts a lot of pressure in one small spot, whereas sitting or crawling on a mattress spreads the pressure out.

Dust mite feces can cause respiratory issues. They feed on organic matter, most commonly human skin, and if you haven't been taking measures to prevent the spread of dust mites, you may have an issue. The older your mattress is, the bigger the problem could be.

There are several things you can do to prevent dust mites:

• Use a hypoallergenic cover on top of your mattress and pillows.
• Wash all of your bedding frequently, and dry it on high heat.
• Keep the humidity in your bedroom low.
• Use a wet cloth to dust; a dry cloth can send dust mites into the air and spread them.
• Get rid of carpets in your bedroom.
• Use a high-quality air purifier.
• Vacuum your mattress occasionally. If you want to get even better results, put baking soda on your mattress and let it absorb moisture and odors for several hours before vacuuming.
• Don't put your suitcase on your bed as you may bring unwanted guests into your bedroom.

An older mattress may lose its ability to absorb the movement of your partner. If you find that you're feeling your partner's shifting more than you have in the past, it may be time to buy a new mattress.

There are several things you can do to help extend the life of your mattress:

1. When moving: carry it so it's parallel to the wall. When you carry it parallel to the floor, it will bend in the middle and damage the mattress.
2. Rotate: every 6 months or year, rotate the mattress to spread out the wear patterns.
3. Flip: only if your mattress can be used on either side. Many mattresses are designed to be used only one way.
4. Cover: using a hypoallergenic mattress and pillow cover will prevent dust mites from getting through the fabric and into the mattress. Clean the pillow and mattress covers in hot water and on high heat to kill dust mites.
5. Bed frame/box spring: make sure that your mattress has proper support. Occasionally check to make sure that if you have wooden or metal slats, that they're not broken or bent. Box springs tend to last for a long time and can often last a couple mattresses (though you should follow protocols for getting rid of dust mites).

If you have a few more years left in your mattress, but you could use a little more support, there are a few things you can do, depending on what type of mattress you have.

If your mattress isn't in too bad condition, there are several things you may be able to do that will give you more time with your current mattress.

1. You could try putting a large piece of plywood underneath.
2. If your bed frame has wooden slats, make sure that all of the slats are not broken and not sagging.
3. You can also try using a mattress cover, which zips around the entire mattress and can help the mattress keep its shape. Many have the additional benefit of blocking allergens from your mattress.
4. Mattress toppers or mattress pads can help reduce any sagging and often make your sleep surface softer.

If you need a new mattress and you don't want to spend the money, you should look at what sleeping poorly could be costing you. Poor sleep affects so many systems in the body that there can be a serious toll:

• lower productivity at work
• higher risk of accidents
• more irritability and moodiness that can negatively affect relationships
• higher risk of anxiety and depression
• lowered self-control resulting in poorer diet and lifestyle
• higher risk of obesity
• poorer memory
• higher risk of Alzheimer's disease
• poorer skin
• lower bone strength
• poorer immune function
• higher rate of inflammation

You could always look at the cost of a mattress broken down over the expected life of the mattress. A memory foam mattress lasts an average of 8-10 years. If you spend $500 on a mattress that will last you 8 years, this breaks down to an average of $62.50/year or $5.20/month. If you committed to buying one less Starbucks coffee every month, you could afford a new mattress.

Throwing your mattress away so it ends up in a landfill is only one option, and it's not great for the environment. There are several other options that are not only better for the planet but may help others.

• Donate: you may know someone who could benefit from your used mattress. If not, there are many organizations that will take your mattress. Make sure it's in relatively good condition, doesn't have bed bugs, and some organizations may even pick it up. Some choices include the Salvation Army, The Furniture Bank Association of America, Habitat for Humanity, or Goodwill. You can also ask local churches or religious organizations, women's shelters, homeless shelters, or refugee resettlement groups.
• Sell: if your mattress isn't in bad shape, and local laws don't prohibit it, you might be able to get a little money for it. Craig's List is a popular option to sell any items you no longer need.
• Recycle: all major North American cities have mattress recycling programs.
• Upcycle: You can break down a mattress yourself and use the materials inside for a new purpose. Box springs can create a wine rack or table. You can get creative and have unique items in your home that came from your old mattress.
• Junk removal service: this option will cost you a little bit of money, but can be convenient, especially if you have other items you want to get rid of.

There are several ways to save money on a new mattress. One is to buy online. Online retailers have much lower costs as they don't have to pay rent for a building or hire salespeople. You don't have the confidence of knowing exactly how it looks and feels unless you've lain on it, so go to brick and mortar stores to identify the level of firmness you want, as well as other features. Once you find a mattress that you like, see if it's sold online. There are several mattress brands that only sell online, but a few have displays in some higher-end stores. If you can't find a mattress in-store that you like, read a lot of reviews and find a mattress that has an in-home trial with a full refund.

Another thing that can save you a lot of money is shopping during sales. Amazon Prime Day, Black Friday, Cyber Monday, and other major holidays are often times that mattresses go on sale.