Like a trusty guard dog, your smartphone probably rests right next to you (or even under your pillow) every night when you go to sleep. You’re able to answer calls, texts and emails at a moment’s notice – even during the wee hours of the night.
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And isn’t that the best part about technology? Always being connected and never truly shutting down or logging off?
Not so fast. You probably don’t even realize how your smartphone habits are affecting your sleep and your brain’s health. What may seem like a harmless habit to you – jumping into bed and opening up your phone – can actually have a big impact on your overall health.
Sleep disorders specialist, Harneet Walia, MD, sheds some light on this sleep-sabotaging habit.
1. It keeps your mind psychologically engaged
Smartphones were designed to make us more productive and our lives easier. They’re designed to entertain us and provide information. But when it’s time to turn off the lights and go to sleep, the last thing our brain needs is more information and more entertainment. (And that seems fair enough – we give our brains enough to think about during the day!)
“Checking your phone stimulates the brain so we are more active and awake,” says Dr. Walia. “Even just a quick check can engage your brain and delay sleep.”
What can make this habit even worse is feeling the need to constantly be connected and available. Dr. Walia warns against the idea that you have to immediately answer, respond, post or scroll. The smartphone era has forced us to feel like we can never really log off, even when we’re sleeping.
Your mind can stay active and engaged long after you’ve scrolled through Instagram or responded to a few work emails. Going to bed and falling asleep should be a peaceful, happy and relaxing experience. Engaging with your phone too close to bedtime can negatively impact those feelings.
2. The blue light from the screen suppresses melatonin
Let’s cut to the chase. The blue light that your smartphone emits is not only bad for your vision, but it’s bad for your brain too. Dr. Walia says that research has found a correlation between suppressed levels of melatonin and exposure to blue light. Melatonin is a hormone responsible for controlling your sleep-wake cycle. So when your body runs low on it, you can experience insomnia, tiredness during the day and irritability.
The blue light from your phone is an artificial color that mimics daylight. This can be great during the day since it can make you feel more alert, but it’s just the opposite of what you need at night when you’re winding down to hit the hay.
Exposure to blue light can affect your internal body clock and throw off your circadian rhythm. This rhythm is in tune to light and dark. It’s why you feel more tired at night when the sun starts to set and why you feel more energized in the morning when it’s light.
Adding in your phone’s artificial blue light right before bed disrupts your body’s internal clock and rhythm.
3. The alerting properties delay REM sleep
You probably know what it’s like to scroll through Facebook right before bed and see something that makes you upset. Even seeing something right before bed that makes you happy can trigger a response that prolongs falling sleep, which consequently delays REM sleep. These emotions can leave you staring at the ceiling for hours feeling wide awake.
Checking your phone right before bed can lead to distracting emotions, thoughts and anxiety, says Dr. Walia.
And it’s not just the alertness you get from late-night social media sessions either. It’s thinking about or feeling your phone going off under your pillow. It’s listening for that email chime letting you know a project is moving along.
Everything about your phone is supposed to make your life easier and entertain you, but what it’s really doing at night before bed is the exact opposite. It’s distracting you, keeping you awake, stimulating your brain and delaying REM sleep.
So what should you do?
If you’re a nighttime technology user, it’s important to set some ground rules for usage closer to bedtime.
Dr. Walia recommends cutting off-screen time 1 hour before bed but says there are even benefits to discontinuing it just 30 minutes before bed. And sure smartphones are typically the main culprit, but even tablets and TVs can emit blue light that can contribute to poor sleep.
It’s important to establish a relaxing bedtime routine and discourage activities that can lead to anxiety or a high emotional response. Dr. Walia recommends choosing nighttime activities that promote sleep.
If you’re really struggling with limiting screen time before bed, try putting your phone in a different room and investing in a clock radio for your bedside table. There are also options within your phone (like setting it on ‘night mode’) to minimize distractions and notifications that can help get you in the mood to snooze.