5 Ways Sleep Affects Your Heart Health

It’s hard to move on to the rest of your day when you get a poor night’s sleep. You’re groggy and cranky, and you want more than anything to crawl back between the sheets. While bad sleep happens to everyone here and there, persistent sleep issues can be a big problem, and they’re not something you want to ignore: They can increase the risk of other health issues – including ones that can hurt your heart.

There are several ways sleep affects your heart health, and some are more direct than others. Lack of sleep can stress certain systems in your body that can make it harder for your heart to work the way it needs to in order to support your overall health. In the same vein, getting plenty of sleep may help boost heart-healthy habits you’re already engaged in.

Sleep is complicated, and this isn’t meant to stress you out even more if you’ve been struggling with it. But if you’ve been having difficulty logging enough shut-eye or haven’t been making sleep a priority in your life, knowing about the potential downstream effects on your heart could push you towards some changes. Here’s what a cardiologist and a sleep medicine physician want you to keep in mind.

Why is sleep important for heart health?

It seems random, but sleep has a lot to do with your heart. “Sleep is so important that it’s recognised by the American Heart Association as one of Life’s Essential 8 components of heart health,” says Dr Jonah D. Garry, a cardiologist and assistant professor.

Sleep is a “reset” for your central nervous system; it allows your parasympathetic nervous system – which controls rest, digestion and energy conservation – to take over to give your body a period of recovery, says Dr W. Chris Winter, a sleep medicine physician and author of The Sleep Solution. If your body doesn’t get that rest at night, you can end up with blood pressure problems, inflammation and metabolic consequences (like obesity or insulin resistance, a condition in which your cells don’t respond as well to insulin, a hormone that helps your body use glucose for energy), Dr Winter says.

Several conditions that affect the heart are linked to lack of sleep

These health conditions can have several causes, but lack of sleep can also contribute, according to doctors.

High blood pressure

Blood pressure naturally goes down at night; this is a normal part of a healthy sleep cycle, and it allows your vessels time to relax and recover. But that doesn’t always happen when you don’t get enough sleep. “Your body may stay in a more activated, ‘fight-or-flight’ state,” Dr Garry says. “This can increase stress hormones, raise your heart rate and cause your blood vessels to tighten, all of which can contribute to higher blood pressure.”

Doctors refer to people with a smaller-than-expected drop in blood pressure as ‘non-dippers,’ says Dr Winter. “It’s not a club you want to be in,” he says. “‘Non-dippers’ have a much increased risk of cardiovascular disease, including [high] blood pressure.”

Obesity

This link is less straightforward, according to doctors. “Sleep also affects hormones that control hunger and energy balance,” Dr Garry says. “When you’re sleep deprived, you may feel hungrier, have stronger cravings for energy-dense foods and have a harder time making healthy food choices.” Lack of sleep can even interfere with hormones that influence how satisfied you feel, putting you at a higher risk of overeating, Dr Winter says.

“Also, when you’re awake a long time, you have more time to eat, and you’re likely too tired to really exercise much,” he says.

Type 2 diabetes

Diabetes causes glucose (that is, sugar) to build up in your blood, which can damage your blood vessels, raising the risk of heart disease, Dr Winter says. And glucose levels can be affected by lack of sleep as well. “Insulin sensitivity and cortisol changes – elevations, spikes – are linked to poor sleep quality and inadequate sleep,” says Dr Winter.

When your body becomes less responsive to insulin, it may make blood sugar harder to control, which may contribute to insulin resistance, he says. That’s important, since insulin resistance is considered a precursor to type 2 diabetes. Cortisol fluctuations can also raise blood sugar and increase insulin resistance, in turn increasing your chances of developing type 2 diabetes.

Insomnia

Insomnia is trouble falling asleep, staying asleep or getting good-quality sleep, per the US National Heart, Lung, and Blood Institute (NHLBI). “Over time, insomnia can cause a lack of sleep, which can affect heart health,” Dr Garry says – for instance, contributing to the high blood pressure and obesity that we mentioned above.

Sleep apnea

Sleep apnoea has a “huge” impact on heart health, Dr Winter says. “It’s common and massively problematic to cardiovascular health,” he says. Obstructive sleep apnoea is marked by breathing that stops and starts at night. When your breathing stops, your oxygen levels drop, and your body activates your sympathetic nervous system and releases stress hormones; this raises your heart rate and blood pressure, which can take a toll on your vessels over time.

Some risk factors for sleep apnoea overlap with those for heart disease, including obesity, age and alcohol use, per the NHLBI.

Addressing sleep issues can support better heart health

Sleep issues are complex, and there’s not one tip or trick that will improve them all. Still, sometimes working on sleep hygiene and simply making sleep a priority can help.

The US Centers for Disease Control and Prevention suggests the following:

• Keeping a consistent sleep and wake time.
• Keeping your bedroom quiet, relaxing and at a cool temperature.
• Turning off electronic devices at least 30 minutes before bedtime.
• Avoiding large meals and alcohol before bedtime.
• Restricting caffeine to the morning.
• Exercising regularly.
• Maintaining a healthy diet.

But if you suspect that your sleep issues are due to an underlying sleep disorder like insomnia or sleep apnoea, doctors say it’s important to get evaluated by a healthcare professional. They can help you figure out what’s going on and suggest a treatment plan going forward to support your sleep – and your heart health.