Hi, I'm Craig, and I'm currently sleep-talking, and this is mental floss on YouTube. Today, I'm gonna answer Sarah F.'s big question, "Can you really be tired from sleeping too much?" 

This is definitely something you hear people say all the time, but it doesn't make much sense. How can you be so tired if you just slept for eleven hours? Let's find out if it's true. (Snoring noises)

(Intro)

(More snoring noises)

So, the short answer is yes, you can be tired from sleeping too much. After sleeping for a long time, people tend to report an increase in lethargy and a decrease in motivation. In fact, the groggy state from sleeping too much has a name: sleep drunkenness. 

In the brain's hypothalamus, there's something known as the circadian pacemaker. This regulates whether you fall asleep and when you fall asleep. It works based on our 24 hour days because it's affected by the light coming in through our eyes, and that becomes a cycle.

So, if that cycle is accustomed to you waking up at a certain time, then it's gonna be disturbed if you sleep a few hours past that time. It'll make you feel like you do when you have jet lag. Like "Ugh when's my baggage coming?!"

And there are more serious risks than just feeling groggy. For example, a study conducted in Finland in 2007 determined that the risk of mortality increases by 20% in people who consistently sleep for longer than 8 hours.

According to Harvard health publications, or HHP, people who regularly sleep for longer than 10 hours have greater risk of heart disease, stroke, type 2 diabetes, and depression.

If you're oversleeping on a regular basis, it may be a sign of another issue, like sleep apnea, narcolepsy, or another sleep disorder, so see your doctor if that's the case.

And all this probably has you wondering, "How much should I actually sleep, Craig? Huh?" Well, the amount is different for every person. It depends on things like age, lifestyle, health, how into Bejeweled you are, when you play it in bed.

If you're over 18 years old, you probably need between 7 and 9 hours. If you're between 11 and 17 years old, you'll need around 8.5 to 9.5 hours. If you're a baby, then you should stop watching this video and go take a nap, 'cause you probably need it, and you probably don't know what I'm saying.

Also, if you're Mitzy, you... basically, like 23 hours. Basically all day. (Affectionate dog cuddling noises)

Thanks for watching mental floss on YouTube, made with the help of these sleepy people. If you have a big question of your own that you'd like answered, leave it below in the comments.

Also, if you have more questions about sleep, I do this other show, right here on YouTube, called "The Good Stuff," link right down there in the dooblydoo. We just did a playlist all about sleep. (Faint squeak in the background) We're really smart. Mitzy is playing with a toy over there, you may have heard it squeak. 

Thanks for watching, see you next week.