Why do cats sleep so much? What are unhealthy sleeping habits? – USA TODAY

Has it ever been the middle of the day and you just needed to shut your eyes for a quick 20 minutes? You might call this break in your day a cat nap. The American and British Academy says the origin of the phrase dates to the 1800s where people started to use it to describe brief rest periods during the day that were similar to cats.
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According to PetMD, on average cats sleep about 15 hours a day. They say some sleep as many as 20 hours a day. A cat’s frequent slumber can be chalked up to a few different biological factors. 
PetMD explains that most cats are active from dusk to dawn, meaning they become more active in the evenings and settle down in the morning. Most likely, when you’re asleep your cat may be getting up to all sorts of mischief and heading off to bed when you’re making your morning coffee. They further explain how cats have “the physiology of a predator, meaning that they’re hardwired to give chase and hunt — mainly at night.” Some large cat species like lions follow a similar pattern of being more active at night and asleep by morning. 
On top of cat’s normal sleeping pattern, protectapet.com explains how cats may sleep more during the winter and other darker months. Cats also may sleep more during cold and/or stormy days. Cats can also become bored causing them to become more sluggish and tired.
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If your cat begins to sleep more than normal in a concerning manner, the Animal Emergency Center advises seeking medical help for your cat. Pawmaw.com explains how other possible reasons for your cat sleeping more than normal may be because they’re lacking in certain vitamins, obese, experiencing depression, dealing with a viral or bacterial infection, poisoned, arthritic or diabetic.

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