Study Links “Night Owl” Sleep Habits to Poorer Heart Health During American Heart Month

February is American Heart Month, and a new study published in the Journal of the American Heart Association is drawing renewed attention to how sleep habits — not just how much we sleep, but when and how consistently — can affect cardiovascular health.

Researchers found that so-called “night owls,” people who naturally stay up late, tend to have poorer overall cardiovascular health compared to early risers. The findings add to a growing body of evidence linking irregular sleep schedules to increased heart risk.

Dr. Lindsay Mitrani, a cardiologist with Optum CareMount Medical, says sleep plays a central — and often overlooked — role in heart health.

“Sleep is crucial for cardiovascular health,” Mitrani said. “There is a bidirectional relationship, meaning it goes both ways. In other words, sleep is really important for preventing key factors that are related to cardiac health, including elevated blood pressure, weight, and feeling well. And the other side of this, cardiovascular treatment can also affect sleep.”

What counts as “good” sleep?
According to Mitrani, adults should aim for seven to nine hours of sleep per night — but quantity alone isn’t enough.

“Almost a third of adults are poor sleepers, meaning they’re averaging less than seven hours, and less than half of adults report having a good night’s sleep,” she said. “That said, it’s not just about quantity of sleep, it’s also about quality.”

Quality sleep, she explained, includes how long it takes to fall asleep, how often someone wakes during the night, and whether sleep is consistent from one night to the next.

How lack of sleep affects the heart
When sleep is short, irregular, or poor in quality, the cardiovascular system can suffer. “When someone’s not sleeping, essentially the blood pressure rises,” Mitrani said. “Blood pressure is a critical risk factor for cardiac health.”

Sleep deprivation also affects daily habits tied to heart health.

“When you’re tired, it’s harder to make good dietary choices. You’re less physically active. You’re not in the mood to go to the gym,” she said. “And even for me or for anyone I know, there’s definitely mood disturbances or irritability when you don’t have good sleep.”

Over time, poor sleep can increase the risk of atherosclerosis — plaque buildup in the arteries that can lead to heart attacks.

Is it timing, quality, or duration? All of the above.
Mitrani says heart health depends on a combination of sleep factors.

“It’s all three together,” she said. “When we think about heart health, we think about not just medications, but lifestyle. What can we do to help keep our heart healthy?”

That includes both getting enough sleep and maintaining good sleep quality. Frequent awakenings, trouble falling asleep, or difficulty staying asleep can all undermine cardiovascular health.
Can night owls “catch up” on sleep?

The study focused on people with late-night sleep patterns, raising questions about whether weekend sleep or naps can offset weekday deficits. Mitrani says irregular sleep itself is part of the problem.

“The irregularity is definitely harmful,” she said. “Having sleep consistency is a key marker for sleep success.”

Still, she emphasizes that many sleep habits are modifiable.

“What we like to talk about is sleep hygiene,” Mitrani said. That includes limiting screen use before bed, dimming phone displays, setting a consistent bedtime routine, and keeping the bedroom cool and dark. “Some people turn their phone on do not disturb, turn down the temperature 68 to 70 degrees, and even turning off the TV to not have something awakening them up in the middle of the night.”

Families, kids, and mismatched sleep schedules
For couples or families where one person is a night owl and another is an early riser, Mitrani says routines can help reset circadian rhythms.

“Studies show you can actually move that up by a couple of hours by setting good routines,” she said, though she acknowledges not everyone can fully adjust.
For children and teens, screen time and caffeine are major obstacles.

“Another big thing is caffeine, especially with teenagers,” Mitrani said. “Trying to limit that later in the afternoon… all of that can be helpful.”

When to talk to a doctor
Mitrani encourages people to seek medical advice if sleep problems persist despite good sleep hygiene, especially because some sleep disorders are closely linked to heart disease.
“One big one is called obstructive sleep apnea,” she said. “That means not just snoring but gasping for air and difficulty obtaining oxygen, which is crucial to your health during sleep.”
She also points to depression and anxiety as common, treatable conditions that can disrupt sleep and affect heart health.

The takeaway
Mitrani says the benefits of good sleep go beyond feeling rested.

“Good sleep can improve your life expectancy up to several years,” she said. “One study said almost five years in men and two and a half years in women.”
Just as important, she adds, is quality of life.

“It can improve your blood pressure, your mood, helping make good dietary choices,” Mitrani said. “All of this is essential to good cardiovascular health.”

Image: A person looks out of a window in an apartment building in Kansas City, Mo., May 3, 2020. (AP Photo/Charlie Riedel, File)