WASHINGTON — While you’re counting sheep, you may need to count the years you’ve be using the same mattress because experts say it has a lifespan.

As the years go by, mattresses can be less comfortable and less supportive. While Consumer Reports says there is no clear time table for when to get a new mattress, it offers tips for when it’s time to go mattress shopping.

• You regularly wake up tired and achy.
• You sleep better when you’re not in your bed.
• The mattress appears saggy or lumpy.
• You’re older than 40 and you’ve have the same mattress for five to seven years. Aging can affect how long you can tolerate the pressure of the mattress.

To get the most life out of your mattress, Consumer Reports gives the following advice:

• Don’t let the kids jump on the bed.
• Rotate your mattress.
• Use a bed frame that has a center support.

In January, Consumer Reports released its list of the best mattresses. Below is the list with the overall score in parenthesis. Scores are on a scale of 100.

1. Serta Perfect Day (72)
2. Beautyrest (71)
3. Charles P. Rogers (68)
4. Sealy (67)
5. Stearns & Foster – Lois Luxury Firm (64)
6. Stearns & Foster -Lux Estate Delana (63)

Consumer Reports ranked the top memory foam mattresses, too.

1. Sleep Number (74)
2. Novaform (69)
3. Bob’s Discount Furniture (63)
4. Tempur-Pedic (62)

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