Most smartwatches and fitness bands offer basic health features like heart rate monitoring, activity, and sleep tracking. Many people use the feature to track their sleep cycle and schedule. Some even end up wearing these smart bands all the time. But is it safe to wear a smartwatch or fitness band while sleeping? And does it affect your health with radiation if worn all the time? Let’s discuss this in detail.
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What is Sleep Tracking on Smartwatches and Fitness Bands?

Taking enough sleep daily is essential for our body to relax the muscles and brain and gain the power back. But sometimes, we get tensed or anxious due to stress, frustration, or other happenings in our daily life. This can cause sleep-related issues and have a negative impact on health.
The Sleep Tracking feature on smartwatches and bands can analyze and tell your sleep duration, quality, and sleep patterns. It can also gauge your sleeping cycles, including rapid eye movement and non-rapid eye movement phases.
This is usually done using actigraphy, i.e., by detecting the movements on your wrist. Some smartwatches also use changes in heart rate to track the sleep cycle.
How Does Sleep Tracking Works?

As mentioned, sleep tracking in smartwatches and bands uses wrist movements to detect sleep. It primarily uses gyroscope and accelerometer sensors to track body movements. It also helps the device detect which sleep cycle you are in or if you are awake.
Some smartwatches use the heart rate sensor to monitor heart rate readings while sleeping. Generally, the heart rate is lower when you’re in a deep sleep. The data will change in different sleep cycles as the heart rate will fluctuate according to your sleep stage.
Should You Wear a Smartwatch or Fitness Tracker While Sleeping?

Wearing a smartwatch or fitness tracker while sleeping can be a personal choice for every person. Some people may not be comfortable wearing a smartwatch during sleep, while some people may already be used to it.
If you are concerned about your sleeping schedule, it’s always good to wear your smartwatch to bed. Using the data and suggestions, you can change your daily routine and take proper sleep to keep you calm, and your body relaxed.
However, some people may find the watch uncomfortable on their wrist while sleeping. This can disturb sleep further. Some may even get skin irritation problems, especially when worn tightly.
If you face any such issues, sleep tracking will do more harm than benefits, and hence, you can avoid wearing the watch. But if not, you can wear it throughout the night to track your sleep data and other health parameters.
Radiation in Smartwatches and Fitness Trackers

Most electronic gadgets emit some radiation. In the case of smartwatches and fitness trackers, it is Electromagnetic Fields (EMF). These radiations are also emitted by smartphones, laptops, and TVs through different variations.
Smartwatches use low-frequency EMF, which are non-ionizing radiations and do not have enough energy. Furthermore, they usually send signals in streams or brief bursts (pulses) for a short period.
As a result, wearable devices expose the user to minimal levels of RF radiation over time. Provided they also equip Bluetooth and or Wifi or cellular connectivity, you can keep them below par with smartphone radiation.
You can read more about wearable technology and safety on the CDC’s website and its relation with cancer on the University of Utah website.
Can Wearing Smartwatch All Time or While Sleeping Affect Your Health?

There are no official claims that a smartwatch affects your health if worn all the time. And again, an average consumer takes enough breaks, be it to remove the watch for charging or while going for a bath.
Given the radiation exposure being way under safe limits, smartwatches and fitness trackers can be worn 24 x 7, provided you’re comfortable doing so and are not sleeping with your head right over the watch.
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Is it Beneficial to Track Your Sleep?

Sleep tracking is definitely helpful and beneficial for people concerned with their overall health. It tracks your sleep cycles and tells you if you are having a good sleep or not. The different stages of sleep are described below:
- NREM (Stage One): This is the beginning stage when your body and brain significantly slows down to sleep. It generally lasts up to 5-10 minutes, and if you are awake during this stage, you may not feel active at all.
- NREM (Stage Two): In this stage, you go into light sleep, and your muscles begin to relax as your body temperature, and heart rate slow down. During this stage, your eyes movement stops, and your brain waves slowly. The sleep spindles start storing memories and shut down your senses to keep your sleep uninterrupted. This stage lasts up to 25 minutes and prepares you to enter deep sleep.
- NREM (Stage 3): This is the deep sleep stage when your muscles and brain are at complete rest. Your body prepares itself by strengthening your immune system and creating bones and muscles during this stage. It is difficult to wake up at this stage, but if you awake, then you may face blurriness and brain waving for up to 30 minutes or an hour. You spend up to 20 to 40 minutes in this stage, and as you get older, you spend less time in this stage and more time in the second stage.
- REM Sleep: This is your dream stage when your brain activity gets much higher, matching or exceeding your brain activity when you are awake. Except for your eyes and breathing muscles, the rest of your muscles enters a state of temporary paralysis. Because of this, your heart rate and blood pressure increase, and you start breathing fastly. The first REM cycle starts after 90 minutes of the first stage and lasts for up to 10 minutes, but the further REM stages will get longer as per how many hours you sleep.
Your smartwatch tracks these stages, and you get to monitor your sleep and check your sleep quality. The smartwatch can also suggest some things you can do to take a sound sleep. This can help you fix the way you sleep.
How to Avoid Issues While Sleeping with a Smartwatch or Band?

There can be several issues that you may have to face while sleeping with a smartwatch or band. Let’s discuss these issues and how to avoid them while sleeping with a smartwatch or band.
Skin Irritation

The first and the most common issue if you sleep wearing a smartwatch or band is skin irritation. There can be situations like your skin is sensitive, or maybe you keep your hands under your head while sleeping, etc.
To avoid this issue, you can remove the smartwatch or band before going to bed for a comfortable sleep. Another thing you can do to fix this issue is loosen the strap of your watch or switch to a more comfortable strap.
Sleep Disturbance

A smartwatch is mainly used to get notifications, alarms, reminders, etc., and for each notification, it vibrates every time. This can create a disturbance while sleeping with any smartwatch or band.
You can avoid the sleep disturbance issue by turning on DND or night mode on the watch. Or you can disconnect your watch from your phone’s Bluetooth and reconnect it in the morning- all the data will remain synced.
Here are different ways you can stop Smartwatch notifications while sleeping.
Headache Issues

While scientists have not yet found any solid link between headache and low-level EMF radiations, some people may feel that wearing a smartwatch 24 hours a day is causing headaches.
If that’s the case, you should ideally avoid wearing a smartwatch all the time. Or better, sort your preferences and wear it only when required- for instance, if your sole purpose is sleep tracking, put it on before going to bed, or if activity tracking is all you want, remove it when you’re not working out.
Wrapping Up- Sleeping With Watch On
This was all about sleep tracking on a smartwatch, how it works and whether you should wear the smartwatch or band when sleeping. We also discussed the impact of smartwatch radiation and other related issues.
To conclude, you need not worry about getting cancer from your smartwatch or band. But again, taking frequent breaks throughout the day is always good to relax your wrist and avoid continuous exposure to the wearable.
Anyways, do you wear your smartwatch while sleeping? How useful is sleep tracking for you? Let us know via comments.