October 27, 2021/Sleep

Does a Bad Night’s Sleep Affect Your Health?

How poor sleep harms you — and how to catch more ZZZs

woman can't sleep at night

You know that sleep is a pillar of good health, along with a nutritious diet and regular activity. Not getting the recommended seven to nine hours of slumber a night can contribute to a host of health problems, from higher blood pressure to an increased risk of obesity.


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But what if your sleep woes happen just occasionally? Can one miserable night of tossing and turning have negative impacts on your health?

Pulmonologist and sleep disorders specialist Samuel Gurevich, MD, explains how a sleepless night affects your mental and physical health — and how to get more shut-eye.

Cognitive side effects of not sleeping

If you were up in the wee hours last night, odds are you’re feeling it today. “Sleep is important because being awake is important,” Dr. Gurevich says. “And one or two nights of bad sleep can impair your ability to function well the next day.”

Too little sleep — even for just one night — can leave you dealing with several unpleasant cognitive effects:

  • Irritability.
  • Daytime sleepiness.
  • Slowed reaction time.
  • Reduced focus and concentration.
  • Problems with memory and attention.
  • Symptoms of anxiety and depression.

Those effects do more than sour your mood (and make you reach for more coffee). “Paying attention to your surroundings and your reaction time are processes that keep us safe and on task,” Dr. Gurevich says.

When those processes aren’t working as well as they should, it can impair your performance at work or school and even put you at risk of car crashes or other accidents, explains Dr. Gurevich.


Physical effects of a bad night’s sleep

When you don’t get enough sleep night after night over the long term, it can lead to all sorts of physical effects — including problems for your heart health.

But even a few missed nights of sleep can take a physical toll on your body, Dr. Gurevich says. “Lack of sleep causes an increase in stress hormones,” he explains. “That triggers your resting heart rate and blood pressure to increase.”

Those changes aren’t usually worrisome if they happen occasionally. “The body and brain recuperate quite well from one or two sleepless nights,” says Dr. Gurevich. “But if it stretches into a month or more, that can have lasting impacts on your heart health, mental health and cognitive abilities.”

What are the health benefits of good sleep?

Sleep isn’t just idle time. Many important body processes are happening while you snooze. A good night’s rest benefits your health and well-being in some important ways:

Brain processing

Sleeping helps to lock memories into your brain. When you’re sleep-deprived, you’re less able to remember things you learned while you were awake. Sleep also helps your brain regulate emotions. That’s why you might feel irritable and moody after a poor night’s rest.

Tissue repair

While you sleep, your body is hard at work repairing itself by releasing proteins and hormones that help restore damaged tissues, including muscles. If you’re sleep-deprived, your body heals more slowly. This tissue repair process is also important for helping athletes build muscle and recover from a workout.


Immune system function

Sleep helps boost your body’s ability to fight illness. During slumber, the body produces cytokines — proteins that direct immune cells to fight inflammation throughout the body.

Researchers have also found that sleep deprivation increases your body’s production of white blood cells, the same response the body shows when exposed to significant stress. That imbalance in your immune system is associated with illnesses such as heart disease.

How to catch more ZZZs

You want to sleep well and get the amount of sleep you need. So why isn’t your brain cooperating? Unfortunately, falling asleep and staying asleep doesn’t always come easily. Dr. Gurevich offers these tips for natural sleep remedies.

  • Set yourself up for success: Make sure you have a cool, quiet, dark environment to sleep in. Avoid bright lights, screens and caffeine before bedtime. And if you exercise in the evening, finish two or three hours before you go to bed.
  • Don’t panic: The more you worry about the sleep you’re not getting, the harder it is to fall asleep. Do what you can to maximize the chances of a restful night. Then do your best not to fret.
  • Treat medical problems: If you’re having trouble falling or staying asleep, talk to your doctor. There may be an underlying cause. Common causes of poor-quality sleep include chronic pain, sleep apnea and thyroid disorder.
  • Consider your stressors: Try to identify stressors and recognize how they’re affecting the quality and duration of sleep. Stress, anxiety and depression are among the biggest causes of tossing and turning.
  • Be boring: If you just can’t sleep, get out of bed and go to a different room, but do something boring. Whatever you do, put down the phone. Don’t watch TV and don’t look at anything that emits light.
  • Treat insomnia: Seeking out a therapist trained in cognitive behavioral therapy for insomnia (CBTi).

“It takes some time to learn these skills,” says Dr. Gurevich, “but it pays dividends over your lifetime.”

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