Do I Really Need 8 Hours Of Sleep Every Night? And 10 Other Things We’re Told Are Mandatory

There’s a lot going on around the world that can cause you to lose sleep. And while there are plenty of doctor-approved methods to help you boost your sleep quality and quantity on a regular basis, it’s important to know that not everything you’ve been told about sleep is true.

Some of the mandatory sleep “rules” you’ve been told time and time again don’t help you snooze after all. To separate fact from fiction (and help you actually know what works), we asked sleep experts about the most common pieces of advice out there. Here’s what you need to know to rest easy:

FALSE: File this as an old wives’ tale, says Rajkumar (Raj) Dasgupta, MD, Assistant Professor of Clinical Medicine at Keck School of Medicine at the University of Southern California. There are some science-backed rules for eating and drinking close to bedtime, though.

“When we talk about eating at night, you want to avoid carbohydrates,” Dasgupta says. He also mentions that it’s smart to avoid taking in too many fluids to avoid midnight trips to the bathroom. The big no-nos: alcohol, sugar, alcohol, carbs, and caffeine.

TRUE: Whether it’s the middle of the night or around bedtime, if you can’t seem to fall asleep in bed, get up. If you stay in your bed awake, it conditions wakefulness there. So throw off the covers, move to another room, and do something else screen-free.

“The bed is only meant for one thing which is sleeping, and if you’re not able to sleep within that 20 minutes or so, leave the bed and do things that are non-stimulating in dim lights,” Dasgupta says.

FALSE: Light, darkness, and the release of the sleep hormone melatonin control your circadian rhythm. The best part: you can control the first two to influence melatonin and change your night-owl tendencies to morning lark quicker than you think.

Research shows that individuals who spent a weekend camping (no screens, fluorescent lights, or blackout curtains) had a rise in melatonin 1.4 hours earlier than usual. Those who camped out for a full week moved their melatonin release 2.6 hours earlier, in part because they were exposed to 13 times as much daylight as usual. If you’re stuck in your home without sunrise views from bed, you can use a lightbox to simulate the sun’s wake-up rays and dim electrical lights to help.

TRUE-ISH: Once you reach age 18, it’s advised to aim for seven to nine hours each night, which is less than what children need. But it’s important to hit this minimum and not go below seven hours because it could lead to losses in cognition and memory. This was shown in a 2018 sleep study conducted by Canada’s Western University, which also states that oversleeping can affect you in the same negative way.

FALSE: Pet parents, rejoice! While Dasgupta is a proponent of co-sleeping with pets, he admits it’s not for everyone. “I love having the dogs in my bed,” he says. “In the olden days, we used to be very black and white saying that no pets in the bed.”

A recent study published in Mayo Clinic Proceedings found that humans who shared a bed or bedroom with their dog did not necessarily compromise their sleep quality as previous studies had proposed.

TRUE: Smartphones, tablets, and other devices emit an artificial blue light that actually prevents the release of melatonin and interferes with your body’s natural internal clock, per the Sleep Foundation. That blue light delays sleep latency by an average of 10 minutes, according to a 2015 Harvard study. Falling asleep in front of a screen, including a TV, creates the same problem.

“What you are watching on your cell phone and what you are watching on your iPad matters because you want to actually transition asleep, both mentally and physically,” Dasgupta says. “Nighttime wouldn’t be the time to be mentally aroused or to have intense emotions or to be angry or sad.”

FALSE: It’s possible for your bedroom to be too quiet, according to Dasgupta. “White noise may be something to help individuals go to bed,” he adds. And white noise doesn’t have to come from a sound machine; it could be a fan running, or a rainstorm outside (which is actually pink noise—it’s a thing!).

FALSE: Dasgupta is pro-nap. “If you’re sleep deprived, which everyone is, I’m a really big fan of napping,” Dasgupta says. He also mentions that the key to a daytime power nap: noise cancelling headphones.

If you’re wondering how much, Dicsosmo suggests that you limit your daytime snooze to 30 minutes for optimal nighttime sleep.

TRUE: A cool room (around 65 to 67 degrees) is one of the three keys to a good bedtime routine, per Dasgupta. “When your body lays down, it should cool down, and when you wake up your body warms up,” he says. “So, you definitely want to go on the cooler side.”

If your room is too hot, it can wake you up. “Sweating interrupts sleep, but keep in mind that everyone’s ideal environmental temperature is different,” Dr. Bruno Dicosmo, MD, Director of Westmed Sleep Center and Pulmonologist, says. “Also, a mildly cold temperature during sleep gives the body a nighttime boost in transforming glucose and fat into energy.”

FALSE: A low intensity cardio session isn’t going to hinder your sleep. “The only time you will have the negative effects of exercising late is if you’re exercising like an Olympic athlete or like LeBron James,” Dasgupta says. Harvard Health research agrees with a study published in Sports Medicine that suggests you can exercise in the evening as long as you don’t do any vigorous activity at least one hour before bedtime.

TRUE: “Keeping a similar sleep time nightly is crucial,” says Dicosmo. “Changing bedtimes or rise times by more than an hour from your usual routine can disrupt sleep and make it more difficult to fall asleep.”