How Sleep Affects Your Mood

Learn how sleep affects your mood, plus ways to improve your sleep habits

By Abby Perkins

Feb 3rd, 2021

Every person who’s pulled an all-nighter (or just stayed out a little later than they should have) can attest to the necessity of sleep – and the harmful effects of not getting enough. According to the American Psychological Association:

“Sleep deprivation taxes the immune system, and is associated with a heightened risk of high blood pressure, heart disease, stroke, diabetes, obesity and depression. People who chronically fail to get enough sleep may actually be cutting their lives short.”

And sleep doesn’t only affect your physical well-being. In fact, there’s a clear connection between sleep and your emotional well-being, too.

What happens when you don’t get enough sleep?

You know what it feels like to wake up after a rough night – that slow, groggy, can-barely-keep-your-eyes open feeling. Your brain’s a little fuzzy and you can’t concentrate. Most of all, you’re annoyed. At everything.

That bad mood you feel when you’re tired? That’s pretty common. When you have poor sleep quality, you tend to feel more sad, irritable, stressed and angry. You’re more emotionally reactive – you might be more likely to snap at someone or take offense. And it doesn’t take much for most people to go from “well-rested and happy” to “tired and cranky” – just one night of bad sleep can have an effect on your mood.

The reason for this link between sleep and mood is likely a little part of your brain called the amygdala, the area that processes your emotions. According to a study published in the Journal of Neuroscience, when you experience sleep loss, your amygdala sees more activity. At the same time, your prefrontal cortex – the part of your brain responsible for decision-making and emotional control – sees less. That combination of brain activity is a recipe for heightened emotions.

Chronic sleep problems and mental health

Sometimes, a lack of sleep can mean more than just waking up cranky. Chronic sleep problems can lead to a higher risk of mood disorders, like depression and anxiety. At the same time, mental health issues can also be the cause of serious sleep deprivation.

Related: How to solve sleep problems using science

Research has shown that 15-20% of people diagnosed with insomnia will develop major depression. Other studies have estimated that people with insomnia are five times more likely to develop depression and 20 times more likely to develop panic disorder. And insomnia is often an early indicator of mood disorders, used to help diagnose depression and anxiety.

Insomnia isn’t the only chronic sleep problem that can lead to mental health issues. Other disorders that disrupt healthy sleep can have a similar effect. People with obstructive sleep apnea – which causes breathing problems to continually disrupt sleep patterns throughout the night – are five times more likely to have clinical depression.

How much sleep do you really need?

Everyone knows you’re supposed to get 8 hours of sleep a night. But is that true for everyone? How much sleep do you really need to get by – and stay happy?

Exactly how much sleep you need can vary from person to person. According to Brandon Peters, M.D. at, “Everyone has a sleep need that is likely determined by genes or genetic information. This need is the amount of sleep our body requires to wake up feeling refreshed. This difference likely occurs across a spectrum, with ‘short sleepers’ needing less than average and ‘long sleepers’ needing more.”

However, the National Sleep Institute does recommend some general guidelines:

  • Newborns (0-3 months): 14-17 hours a night
  • Infants (4-11 months): 12-15 hours a night
  • Toddlers (1-2 years): 11-14 hours a night
  • Preschool-age children (3-5 years): 10-13 hours a night
  • School-age children (6-13 years): 9-11 hours a night
  • Teenagers (14-17 years): 8-10 hours a night
  • Young and adults (18-64 years): 7-9 hours a night
  • Older adults (65+ years): 7-8 hours a night

Not getting close to the recommended amount of sleep for your age range? You’re not alone. According to a Gallup poll, 40% of Americans are getting less than 7 hours of sleep a night.

Improving your sleep (and your mood)

If you tend to fall short of your recommended sleep, don’t panic – or reach for the sleeping pills (yet). There’s a lot you can do to combat unhealthy sleep habits and boost your mood.

These tips for better sleep can help get you back on a more normal schedule and improve your sleep:

Stick to a schedule

Repairing your sleep hygiene and making an effort to go to bed and wake up at the same time (yes, even on weekends) can help your body’s clock adjust to a healthy sleep schedule. 

Limit naps

It’s tempting to nap when you’re low on sleep, but it doesn’t actually help in the long-term. Skip the naps and go to bed when you’re tired at night instead. 

Create a bedtime routine

When you’re still alert and active from the day, you’re not ready for bed. As Professor of Sleep Medicine Colin Espie recommends at, “The answer is to consciously set aside time each evening to relax before heading to bed, and plan a wind-down routine to follow.” Create a bedtime routine that’s relaxing for you – whether that’s meditation, a walk or a good book. 

Set up for sleep

To foster a good night’s sleep, your room should be comfortable, relaxing and clean. Lisa Artis at The Sleep Council advises, “Create a sanctuary to sleep in. Messy bedrooms make for a messy mind, so de-clutter.” Keep your room neat (that means making your bed, too!) and eliminate outside lights and noise. Plus, make sure you’re sleeping on the best mattress for you. You can take our Mattress Finder Quiz to help you find what’s best.

Avoid caffeine, alcohol, and nicotine

Don’t worry – no one’s going to take away your morning coffee. But the more you cut out these sleep-interfering chemicals, the faster you’ll be able to fall asleep.   

Plan your exercise and meals

Regular exercise and a healthy diet can actually help you sleep better. But don’t exercise or eat too close to bedtime to make sure your body is relaxed and ready to rest.

And if you’ve tried these tips, but it’s still not doing the trick, there are still other natural remedies for getting better sleep.

There’s no doubt that being short on sleep affects your mood – and that serious sleep issues can lead to even bigger problems. But it’s not all bad. Take steps to improve your sleep habits, and you’re likely to see immediate improvements in your mood and your emotional well-being.

How does sleep (or lack of sleep) affect your mood and quality of life? Let us know in the comments below.