Is Staying Up Late Bad for You?

Night owls are people who go to sleep late instead of getting up early in the morning. Here are 14 reasons why getting to bed in the wee hours may be bad for your health.

Higher Blood Pressure Link

Night owls are more at risk for high blood pressure (hypertension) than people who don't stay up late, according to Andrew Varga, MD, assistant professor of medicine, pulmonary, critical care, and sleep medicine at Icahn School of Medicine and Mount Sinai Health System. This common condition happens when the force of the blood against the artery walls is too high, according to the National Heart, Lung, and Blood Institute. Lifestyle patterns such as unhealthful eating or lack of exercise (see below) may contribute to night owls' higher likelihood of hypertension. Stress—both physiological and psychological—may play a big role, as well.

Less Likely to Workout

Researchers for an April 2022 study published in the Health Promotion and Chronic Disease Prevention Journal investigated the link between children's and adolescents' sleep timing and health indicators. They found that the later the sleep time, the higher incidence of sedentary behavior.

Most fitness experts agree that the best time of day to exercise is different for everyone. But getting up early and working out first thing does have its advantages: A morning workout can help you make better wellness choices all day, and you may even lose more weight. According to a 2019 study in the International Journal of Obesity, people who exercised earlier in the day (at least before noon) lost "significantly more weight" than people who exercised later in the day, past 3 p.m.

May Lead to Weight Gain

"When people go to bed late, they're up living their lives—and one of the things they're often doing is eating," said Dr. Varga. "If your bedtime is 3 in the morning, you're probably eating around 11 p.m. or midnight, and that's been known to create problems with the way your body handles and metabolizes food."

Some experts believe that eating after dark disrupts the body's natural overnight fasting period, which can interfere with its ability to burn fat. Night owls can also consume more calories–perhaps because willpower is lower when we're tired and we tend to crave unhealthful foods late at night.

Higher Risk of Developing Diabetes

Type 2 diabetes is a serious condition, particularly when it comes to night owls. In fact, in a January 2022 meta-analysis published in Advances in Nutrition, researchers discovered that across 39 studies, night owls had "a significantly higher risk of diabetes" along with other conditions.

Challenges Managing Diabetes

If you have diabetes, being a night owl can make the condition more difficult to manage. It is important that "[t]he benefits of consuming meals early in the day should be encouraged in (people with diabetes)," according to a February 2020 Nutrition & Diabetes study.

"We know that the amount of sleep you get is important, but this research is also suggesting that when you're sleeping matters, too," Kristen Knutson, PhD, associate professor of neurology and preventative medicine at the Northwestern University Feinberg School of Medicine, told Health. Also, research published in Sleep Medicine Clinics in December 2015 found that people with diabetes showed a link between evening chronotypes (a person's time preference for activities) and unhealthy cholesterol levels.

Less Sleep

Night owls tend to get less overall sleep than those who are early-to-bed, early-to-rise. "If you can't fall asleep until 2 or 3 in the morning and you have to be at work at 9, you're not going to be able to get as much good-quality sleep as you really should," said Dr. Varga.

Night owls with weekday jobs tend to make up for some of that lost sleep on the weekends, when they can sleep in. This type of "sleep debt" isn't that easy to catch up on, but shifting your sleep schedule on the weekends could still come with health risks of its own.

More Risk-taking

Staying up late and sleeping in every morning is also associated with a greater tendency for risk-taking, according to a 2019 study in PLoS One. In general, the male participants in the study reported that they took more risks than the female participants. However, the female participants with evening chronotypes reported taking more risks than their morning counterparts.

While taking risks isn't always a bad thing, it can sometimes lead to dangerous or unhealthful situations. In a 2021 study in Europe's Journal of Psychology, authors noted that risk-taking included "self-challenging" or socially accepted behavior like trying a new sport, standing by what you think is right, or performing in front of an unknown audience. But risk-taking also included dangerous or illegal behavior, such as fast driving, binge drinking, or stealing—defined by experts as "negative risk-taking."

Early-morning Driving May Be Dangerous

It makes sense that night owls tend to be more tired and less alert in the morning, compared to how they feel during their prime evening hours.

A June 2014 study from Accident Analysis & Prevention, which tested 29 graduate students on driving simulators, found that evening types were less attentive and more prone to errors at 8 in the morning than they were at 8 in the evening. Morning types, on the other hand, were more consistent and drove relatively well during both times of the day.

The authors said their findings suggested that employers should tailor individual work schedules around employees' chronotypes to cut back on people having to drive or perform work-related tasks during "non-optimal" times.

Challenging for Teenagers

It's not uncommon for teenagers to have trouble falling asleep before 11 p.m., according to the National Library of Medicine. School responsibilities and social distractions are two big reasons, but hormonal changes around puberty can also have a lot to do with teens' shifted sleep schedule.

A February 2021 study published in the Journal of Youth and Adolescence investigated the sleep-wake timings for 349 adolescents. The researchers found that teenage night owls—males in particular—engaged in more risky behaviors and substance use than teens who didn't stay up at night.

Linked to Depression and Poor Mood

If you're a night owl, you may be prone to experiencing mood-related issues. Researchers of a March 2021 Biomolecules study noted that those who prefer awake time during the evenings are "predisposed" to conditions from mood disorders to personality disturbances.

Researchers have also suggested that night owls may have a harder time regulating their emotions. In a 2017 study in the Journal of Biological Rhythms, scientists found that night owls are more likely to suppress their feelings and less likely to practice cognitive reappraisal (the ability to change the way one thinks about something—to "look on the bright side," for example) than morning people.

Associated With Alcohol and Tobacco Use

A night-owl lifestyle often goes hand-in-hand with other unhealthful behaviors. A 2020 study in Chronobiology International found that young people who prefer to stay up late are more impulsive than their peers who go to bed earlier, which makes them more likely to drink alcohol and smoke.

Additionally, a July 2021 study published in Genes linked evening chronotypes with increased beer intake.

Of course, that's not true for all night owls, and there's also no evidence that staying up late actually leads to these behaviors. "It's not clear whether staying up late is a cause or a result of these other lifestyle issues," said Dr. Knutson. "In fact, if you're staying up late because you can't fall asleep, these unhealthy behaviors might be a big part of the problem."

May Be Linked to Earlier Death

Even with all of this research, it hasn't been clear whether the health risks associated with being a night owl are substantial enough to make a measurable difference in people's lives.

"We have evidence to show that staying up late also seems to be connected to early death or mortality," said Dr. Knutson. In fact, a 2018 study published in The Journal of Biological and Medical Rhythm Research found that people who like to stay up late and have trouble getting out of bed in the morning have a 10% higher risk of dying sooner than people who have a natural preference for going to bed early and rising with the sun.

Not All Bad News

There are some upsides to being a naturally late sleeper. Night owls tend to have bigger social networks. Research from Aalto University in 2015 analyzed anonymous mobile phone data to conclude that night owls tend to have wider social networks than morning persons and are also more central in their own networks.

Dr. Varga also pointed out that plenty of night owls lead healthy lives and that more research is needed to determine the real-life consequences of staying up late.

"The true data on this is not very strong, and a lot of it is extrapolated from people in extreme situations, like shift workers," said Dr. Varga. "It's still not clear how serious the risks are for people whose patterns may be just a few hours off, so I think some caution is warranted when you're interpreting these studies."

What Night Owls Can Do

Your chronotype may be ingrained in your DNA, said Dr. Knutson, but that doesn't mean you can't change it. "About 50% is genetic, but that leaves another 50% where there's opportunity for shifting your clock. But it does require vigilance and consistency with your schedule, which can be a challenge to maintain."

Night owls can gradually acclimate themselves to an earlier bedtime by turning in a few minutes earlier every night, she said. (Don't rush it too quickly, or you'll lie awake for hours.) It's also important to avoid bright light at night and to wake up at the same time every day.

Exposing yourself to bright light first thing in the morning can also help reprogram the brain to wake up—and subsequently fall asleep—earlier, said Dr. Varga. You can also ask your healthcare provider about taking melatonin, a synthetic version of the brain's sleep-inducing hormone, which is key in regulating your internal clock.

But will shifting the body's natural chronotype actually protect against some of the health risks of being a night owl? "We don't know the answer to that yet, and that's where the research needs to go next," said Dr. Knutson. "For now, I think it's most important for night owls to recognize that they seem to be more vulnerable to the consequences of a less healthy lifestyle, so they need to be even more vigilant about making smart choices."