We all know the importance of getting seven to eight hours of snooze time at night. The reality is, though, those hours don’t mean much if you’re waking up not feeling rested to start your day.

If that’s the case for you, then chances are you aren’t getting enough quality sleep. In order to reap the benefits of sleep, counting solely on the number of hours you spend catching Z’s won’t do you much good—even if you think you slept well.

The first step to improving your shuteye is understanding what we mean when we talk about sleep quality. Keep reading to find out what sleep quality is, how sleep quality is measured, and what you can do to improve your sleep quality.

What is sleep quality?

Sleep quality and sleep quantity are two different things. Sleep quantity measures how much sleep you get every night, while sleep quality measures how well you sleep.

Sleep quality also shouldn’t be confused with sleep satisfaction, which is your own perception of how well you sleep. Many lifestyle factors contribute to sleep quality, including living with certain health conditions, what you eat or drink before bed, your sleep environment, and how you manage stress.

For example, a September 2017 study in the Journal of Epidemiology and Global Health showed that high stress levels are associated with poor sleep quality. Researchers found that medical students who weren’t suffering from stress were less likely to have poor sleep quality, while the risk of poor sleep quality was almost four times higher in those who had a much lower GPA.

How do you measure quality of sleep?

It can be a little tricky to determine your sleep quality—but with some careful attention to your sleep, you can quickly figure out just how restorative—or not—your shuteye actually is. Here are the four main things to look at it when it comes to measuring sleep quality:

• Sleep latency refers to how long it takes you to fall asleep once you’re in bed. According to the Fundamentals of Sleep Medicine, normal sleep latency is between 10 and 20 minutes. The sleepier you are before lights out, the faster you’re going to fall asleep. But sometimes a faster sleep latency can indicate sleep deprivation. For example, those with hypersomnia, a sleep disorder characterized by excessive daytime sleepiness, may have a sleep latency of fewer than eight minutes.
• Sleep waking is how often you’re interrupted from sleep during the night. Waking up frequently at night disrupts your sleep cycle, in which you alternate between non-rapid eye movement (NREM) and rapid eye movement (REM) stages of sleep throughout the night. It’s important to go through four to six sleep cycles at night to get restorative sleep. When your sleep cycles are interrupted, you’re at a higher risk of not getting quality sleep.
• Wakefulness is how many minutes you’re awake during the night after you fall asleep. Generally, those with good sleep quality are awake 20 minutes or less. It’s normal to wake up two to three times a night for 30 seconds to a minute, but you should be able to roll over and fall back asleep pretty quickly.
• Sleep efficiency measures how much time you’re actually sleeping versus the time you spend trying to fall asleep. Ideally, you want to spend 85% of your time asleep.

Use this formula to determine your sleep quality

If you’re wondering what your quality of sleep is, there’s a formula to figure it out. Here’s how to do it: Identify your total time in bed (in minutes) and subtract how many minutes it took for you to fall asleep as well as how many minutes you spent awake in the middle of the night. This is how much time you’re actually asleep at night. Then, take this number and divide it by your total time (in minutes) in bed. Finally, take that number and multiply it by 100 to get your sleep efficiency percentage.

For example, let’s say you spend about 420 minutes (seven hours) in bed at night. It takes you 30 minutes to fall asleep and you spend another 30 minutes awake during the night. That’s 360 minutes you’re actually sleeping at night. Now, divide that number by 420, which is .85. Multiply that by 100 and you get 85% sleep efficiency.

Sleep quality formula: Identify your total time in bed (in minutes) and subtract how many minutes it took for you to fall asleep as well as how many minutes you spent awake in the middle of the night. Take this number and divide it by your total time (in minutes) in bed. Take that number and multiply it by 100 to get your sleep efficiency percentage.

By taking into account these four factors, you can gauge just how good or poor your sleep quality is. Being diligent about making changes to your lifestyle to support these tenets of sleep quality can help you feel rested and energized the next morning.

What is poor sleep quality?

With the four tenets of sleep in mind, some signs of poor sleep quality are taking longer than 20 minutes to fall asleep, waking up frequently during the night, and not being able to fall back asleep quickly if you wake up.

Another red flag is feeling tired in the morning, even after you get the recommended amount of sleep for your age. For example, adults aged 24 to 64 years old should get seven to nine hours of sleep at night.

As mentioned, many lifestyle factors can contribute to poor sleep quality, such as age, subpar sleep hygiene, sleep disorders or health conditions, having young children, and occupation.

Poor sleep hygiene

What you do during the day can affect how well you sleep at night. For example, consuming too much caffeine and alcohol can affect your ability to fall and stay asleep.

Drinking too many caffeinated beverages, such as coffee, tea, soda, and energy drinks, throughout the day can keep you wide-eyed through the evening. And although alcohol is a sedative and may help you fall asleep quickly initially, it can cause more sleep wakings and make it difficult for you to fall back asleep.

Moreover, exposing yourself to a lot of blue light from your phone (raise your hand if you’re guilty of scrolling through Instagram late at night), computer, or TV before bed can interfere with your melatonin levels (the sleep hormone), making it harder for you to fall asleep when you’re ready to hit the hay.

Eating high-fat foods, such as cheeseburgers and fries, and heartburn-triggering dishes, like spicy hot wings, can also keep you up tossing and turning.

Additionally, not going to bed and waking up at the same time can mess with your circadian rhythm and disrupt how your body regulates sleep and wakefulness. Parents of babies and small children, and those who work night shifts or have irregular work schedules, like doctors, nurses, and people who work in hospitality or retail, are prone to having irregular sleep.

Health conditions and sleep disorders

People who live with sleep disorders, like sleep apnea and insomnia, have a harder time getting good quality sleep at night. People with sleep apnea, for instance, may wake up gasping for air during sleep, and people living with insomnia from anxiety or depression may find it difficult to fall and stay asleep.

Having a thyroid disorder, like hyperthyroidism (an overactive thyroid), can also make you feel more anxious and increase your body temperature, making it difficult to snooze well. On the other hand, people with diabetes may experience interrupted sleep at night from restless leg syndrome, peripheral neuropathy, and excessive thirst.

Age

As you age, your body undergoes changes to your metabolism and hormones that can affect your sleep quality. For example, taking certain medications may cause older adults to wake up frequently during the night to pee.

Older people are also more likely to develop insomnia because they live with chronic pain from arthritis or fibromyalgia and have back or hip pain.

Poor quality sleep can lead to a variety of negative health effects, including stress, anxiety, depression, a weakened immune system, and decreased cognitive function. So it’s important to address these issues head-on and work toward making lifestyle changes that’ll improve your sleep quality.

How to improve your sleep quality

Although there are certainly some things beyond your control, there are steps you can take to improve your sleep quality and support consistent and restorative sleep.

• Limit screen time one to two hours before bed and schedule a nightly shut-down to remind you when to shut off the TV and put away your phone and laptop. Or you can use blue-light-blocking glasses and put your phone in night mode, which reduces the brightness.
• Avoid caffeine and alcohol before bed because they can negatively impact your melatonin levels and make it challenging to fall or stay asleep.
• Eat foods high in calcium, magnesium, potassium, tryptophan, and vitamin B6, which are key nutrients that support better sleep quality.
• Adopt a relaxing nighttime routine that helps prepare your body for sleep. Doing a quick and light yoga flow, taking a soothing bath, meditating, and writing in a journal can help you tap your parasympathetic nervous system and de-stress.
• Work with your doctor to address underlying health conditions and medications that are wreaking havoc on your sleep quality. Your doctor may recommend a new treatment plan to help relieve symptoms.
• Create a comforting sleep environment. Adjust the temperature in your bedroom to be between 60 and 67 degrees Fahrenheit, use a white noise machine to block sounds that may disturb sleep, add breathable yet cozy sheets to your bed, and invest in a high-quality mattress. Saatva offers a wide range of high-quality mattresses to suit every sleep style. Take our online mattress quiz to find your perfect match!

This article originally appeared on Saatva.com and was syndicated by MediaFeed.org.

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