Have you ever been guilty of going to bed with your lights on? Maybe you were too sleepy to get up and flick the switch, or maybe you thought brightening your space would help keep away any monsters. Sleeping with the lights on might seem innocuous, but it’s more dangerous than you think for your mind and body. From disrupted sleep to adverse effects on health, those light bulbs can wreak havoc where darkness can actually provide more beneficial results.
Sleeping is one of the most essential activities that humans do on a daily basis—through sleep, our bodies repair, our brains process and digest information, and we prepare ourselves for whatever is coming next. Unfortunately, light—even in small doses—could absolutely derail our natural physiological and psychological activities. Here are seven reasons why you’ll never want to sleep with the lights on again. By the end of this article, you’ll understand how and why sleeping in pure darkness can enhance sleep quality and overall health (and why that little switch is more important than you think).
Reason 1: Lights Disrupt Your Sleep Cycle
That’s right—your body has a clock. It’s called the circadian rhythm, which informs you when to wake up, when to be hungry, and when to feel tired. The circadian rhythm is also significantly influenced by light and darkness; in other words, when you sleep with the lights on, you throw its pathways out of whack. For example, when it gets dark outside, your body begins producing melatonin—the hormone responsible for getting you to sleep. When you sleep with the lights on, however, this process is disrupted.
Light—specifically bright light or blue light—tells your brain that it is daytime. Therefore, melatonin doesn’t circulate, and falling asleep and staying asleep becomes increasingly difficult. Yet even if you do fall asleep, the sleep you get is horrendous. When you wake up the following day, you feel exhausted—like you never slept at all. According to research, exposure to light can reduce melatonin levels by 50%—that’s an essential number when considering how well we sleep.
Think about it. How many times have you struggled to fall asleep with the lights on? Your body expects darkness. Therefore, the longer you force your body to fight against natural inclinations, the more you’re at risk for chronic sleep deprivation supported by increased irritability. Turn the lights off, and you sleep better because your body can function as intended and access those deeper sleeping abilities.
Reason 2: It Can Affect Your Mental Health for the Worst
Sleep and mental health are inherently connected. If you’re not sleeping enough or sleeping well, you’re not in a good mood. When you sleep with the lights on, you take this to the next level as you impede attempts to achieve soothing, quality sleep. Poor sleep is correlated with poor stress management, disordered anxious thinking, and elevated depression levels.
Staying stimulated or somewhat awake when exposed to light at night is never good for calming people down—and over time, it can lead to constant feelings of frustration. Lights at night disrupt sleep cycles all the time, and your mental state will suffer. Studies show that people who sleep in well-lit locations are more likely to complain about feeling anxious and low when awake; One study even found that low exposure to light during the nighttime increased participants’ levels of depression after only a few weeks.
Now, let’s say you wake up in the morning feeling fatigued. This is what happens to people who get an inadequate amount of sleep. Nighttime darkness allows your brain to ease into a restorative state and remain there, which is needed for proper emotional regulation. So, when you turn off the lights, you allow your brain to need what it needs to reset and be in a functional (and coping) state with society during the day.
Reason 3: It Negatively Impacts Your Health
Keeping the light on doesn’t just hurt your mind; it hurts your body, too. Much of the healing that occurs happens during sleep—from repairing bodily tissues to bolstering immunity and regulating hormones. Light at night creates light where there shouldn’t be any, complicating these biological processes for however long it might be.
For instance, light-induced melatonin disruption goes beyond just sleep. Melatonin is also an antioxidant, meaning it protects your cells from deterioration. Having less melatonin puts you at a higher risk for cardiovascular disease and diabetes. One study that noted people who sleep with the light on had a 22% higher risk for being obese because sleeping with the lights on also affects hormonal levels that determine hunger.
For one, your eyes suffer. Sleeping with the lights on means your eyes are always open, leading to strain over time, possibly resulting in eye discomfort or issues. In addition, when you don’t get enough sleep because of exposure to light, your immune system weakens, probably putting you at risk for developing the common cold or viruses. When you sleep with the lights off, you allow your body to function as it should and remain healthfully preventative.
Reason 4: It Impacts Your Ability to Keep the Weight Off
Are you having trouble keeping off weight these days? You may be sleeping with the lights on. While that sounds a bit absurd, recent studies have found that sleeping with the lights on drastically impacts your hunger and metabolism hormones.
Sleeping with the lights on increases levels of ghrelin—your hunger hormone—and decreases levels of leptin—the hormone that makes you feel full. Therefore, when people don’t sleep well, they get hungrier and fail to realize when to stop eating. Moreover, those who eat later at night tend to fall into the category of sleeping with the lights on. Studies show that sleeping with the lights on tends to give people a higher chance of acquiring body weight over time. For example, in one study with women over five years, those who fell asleep with lights on in their bedrooms were 17% more likely to gain 10 pounds or more in the study period.
Think about those late-night snacks you might crave, whether it’s cookies or chips or anything else. Are you using your bedroom lights as an excuse? Darkness stabilizes hormones and prevents such cravings. For every ten hours of darkness, your appetite can go to bed—as in, when you are turning off the lights, you’re ensuring yourself a good night’s sleep and a better likelihood of keeping off the extra pounds.
Reason 5: It Impacts Your Skin
Skin loves sleep. When you rest at night, your body makes new skin cells and repairs everything so that you wake up looking alive and youthful. But when you sleep with the lights on, you make your skin feel tired and dull.
Don’t forget about melatonin—the hormone that helps you sleep. Well, it also serves to protect skin from damage. When your melatonin levels drop, due to light, your skin no longer has that advantageous protective quality. Plus, when you don’t sleep well due to light exposure, this increases stress hormones like cortisol which causes breakouts or worsens sensitivities to skin like acne. In fact, research shows that disrupted sleep patterns can increase skin aging meaning more wrinkles down the line.
Have you ever had a bad night’s sleep and woken up groggy with bags under your eyes? That’s light exposure. When it’s dark, your body can focus all its resources on repairing itself. You wake up looking fresh faced and younger. If you want your skin to remain nice and bright, you should turn the lights off at bedtime.
Reason 6: It Wastes Energy and Money
Additionally, sleeping with the lights on wastes energy and electricity—and money for your monthly bills. Not only are you wasting constant electricity by sleeping and leaving lights on, but this excess energy waste impacts your electric bill, too. Depending on your type of bulbs’ usage, this could be several dollars more a month or beyond.
For example, one 60-watt incandescent lightbulb left on for eight hours during the night uses approximately 14 kilowatt-hours per month. At an average 13 cents per kilowatt-hour, that amounts to nearly $2 per lightbulb. If you have lights or multiple bulbs on, this price compounds quickly. Even LED bulbs still use energy—even if they’re more efficient—so it’s better to turn them off.
Reason 7: It Can Disturb Others
In addition to affecting your wallet, keeping the lights on is bad for those around you. Most likely, if you have a bedroom where you’re sleeping, you’re sharing that room with someone else—a spouse, a roommate, or even a pet. Keeping the lights on at night affects others in your environment negatively. Just like you, light prevents sleep for anyone or anything attempting to fall asleep around you. This complicates social relationships and can create conflict.
For instance, if your girlfriend has to go to sleep during the day because she works third shift, and you’re leaving the lights on to watch TV, she won’t appreciate it. Or worse, she’ll wake up in the middle of the night because your bright reading light is blaring. This will cause arguments as she’s trying to get her beauty sleep, and you’re preventing her from doing so. It’s even worse for your pets. While you may think a light is acceptable for that family puppy who watches you, it disrupts his sleep cycle. When he’s looking to settle down for the evening, a light may annoy him causing him to bark or be restless.
Therefore, keeping the lights off is a good way to ensure a dark, peaceful atmosphere for anyone else in the room with you. It shows you appreciate their ability to sleep, and when everyone gets better rest, things are easier in the morning and everyone is happier. Lights off fosters good relations
How to Achieve a Dark Sleep Space
Now that you understand how detrimental sleeping with the lights on can be, how do you achieve the proper sleep space? Turn off all lamps, overhead lights, and even illuminated screens from your computer and other electronic devices. If you must have some sort of light for safety, use a dim red or amber nightlight as those are least likely to disrupt melatonin production.
If you find that you have street lights shining in while you sleep or an early wakeup call from the sun, consider investing in blackout curtains and shades which will eliminate almost any light infiltrating your new slumber abode. If that’s not an option, at least consider a sleep mask.
Either way, turn off devices and lights at least an hour before sleep anyway, and do a final check around your room at night to ensure a seamless transition into sleep.
Conclusion
Sleeping with the lights on may not seem like something so difficult for you to achieve or avoid achieving that would make your life better, however, doing so impacts your life immensely. For one, sleeping with the lights on disrupts your circadian rhythm, causing significant a array of physical and mental health issues down the line. For two, sleeping with the lights on can lead weight gain, skin issues, increased expenses, and relationship problems. Luckily, all it takes to fix all of this is turning out the lights.
Sleep in a dark room, and you give your body a higher likelihood of restful and successful sleep. Rested bodies are more energized, awake, and healthy. So take the time to turn off the lights before bed; your body will appreciate it, and you’ll be refreshed for whatever tomorrow brings. Why not?