Why Sleep Deprivation Can Hurt Your Heart

Frequent late or even sleepless nights? You are not alone. In 2021, Singapore was found to be the most fatigued country in the world in a survey by Sleepseeker, beating out countries like Japan and China as noted in this CNA article. Another article references a 2020 survey where Singaporeans, on average, were found to get only 6.9 hours of sleep a night. Did you know that lack of sleep not only affects your cognitive abilities and mood, but can also negatively affect your heart and increase blood pressure?

What Are The Stages Of Sleep

During sleep, your body cycles between four different stages, one where Rapid Eye Movement (REM) sleep takes place, and three where Non-REM sleep takes place.

Upon falling asleep, the first stage of sleep occurs for between one to seven minutes. This stage is where the body is not yet fully relaxed, with body and brain activity beginning to slow.

The second stage of sleep is where the body relaxes further, causing a reduction in body temperature, breathing and heart rate. This stage makes up half of the time you spend asleep.

Proceeding to the third stage, the body relaxes even further, and is associated with being critical to quality sleep. This stage allows for physical recovery, growth and improves bodily functions.

The final stage is REM sleep, unlike the previous stages, brain and body activity pick up, almost as if you were awake. Heart rate speeds up in this stage and breathing may becomes irregular. This stage is where your brain processes emotions and learning that happened during the day.

How Sleeping Helps Your Body Recover

During non-rapid eye movement sleep (NREM), your heart rate and breathing slow down, your blood pressure also drops by 10 to 20% while in this stage of sleep. This gives your heart time to recover from strain it may have suffered during the day. However, when you do not get enough sleep, your heart does not have sufficient time to recover leading to negative effects.

How Much Is Too Little Sleep

In a study involving over 400,000 people, those who slept less than seven hours a night were shown to have a higher risk of heart failure. People who suffered from insomnia, daytime sleepiness and snoring were also found to have an increased risk of heart failure, mood/cognitive disorder and elevated blood pressure.

Another study found that people who got less than six hours of sleep per night had a 20% higher risk of suffering a heart attack and an increased risk of stroke.

Impacts That Sleep Deprivation Has On Your Heart

Sleep deprivation contributes to atherosclerosis, also known as coronary artery disease. This is caused by inflammation which is a common symptom among sleep deprived people where white blood cells start to collect in the arteries leading to plaque formation and hardening. This buildup of plaque in your arteries hardens and narrows them, affecting the amount of blood and oxygen the heart can receive.

Risk of heart attacks also increase with lack of sleep. When your body goes through the different stages of sleep, your heart slows and quickens with each stage. However the balance between each stage can be affected by sleep deprivation resulting in a higher risk of heart attacks. Abrupt waking can increase heart attack risk, as heart rate and blood pressure normally spike upon awakening. When these awakenings happen constantly, this can induce stress on your heart and heighten your heart attack risk.

How To Reduce Your Risk

The United States CDC recommends:

• Creating and committing to regular sleep schedule by going to bed the same time each night and getting up at the same time each morning. Doing this even on weekends can help you get better sleep.
• Participating in physical activity during the day can also help improve your quality of sleep, just ensure not to exercise a few hours before going to bed.
• Using a blue light filter on your device a few hours before bed can help you get to sleep easier as well as avoiding artificial light.
• Keeping your room dark, cool and quiet can reduce difficulty sleeping and waking up in the middle of the night.

The Singapore Heart Foundation recommends seven or more hours of sleep per night, adding that one additional hour of sleep per night can reduce the risk of heart attack by 20 percent.

Make Sleep a Health Priority

With Singapore as one of the most sleep deprived countries in the world, managing and improving sleep is even more vital in preventing heart-related conditions. This can be done by making sleep a priority in your life. Taking steps like maintaining a sleep schedule and ensuring a conducive environment for rest can go a long way in improving your long term heart health. You can also monitor your heart health through home blood pressure monitoring, as a way to ensure your blood pressure is within a healthy range, and to detect potential issues.