Ask LH: Is It Safer To Have My Phone In Flight Mode When I Sleep?

Ask LH: Is It Safer To Have My Phone In Flight Mode When I Sleep?

Hey Lifehacker, Is it true that you shouldn’t keep your mobile phone near your head while sleeping? I want to purchase a sleep cycle app that requires keeping the phone under my pillow. Obviously, I don’t want this to affect my health. Would it help if I kept it in airplane mode each night before bed? Thanks, Sleeping Unsoundly

Phone sleep picture from Shutterstock

Dear SU,

There’s currently no hard proof that RF-EMF transmissions from mobile phones cause brain cancer or any other serious health issue. Unfortunately, the evidence is equally inconclusive in the other direction.

A couple of years ago, a multi-disciplinary expert panel organised by the International Agency for Research on Cancer reviewed all published studies on the topic to determine the level of risk. Somewhat worryingly, they concluded that radiofrequency electromagnetic fields are “possibly carcinogenic to humans”.

Now before you freak out, the key word here is “possibly” — the scientific evidence linking mobile phone use to brain tumours is far from conclusive. It’s worth noting that global brain tumour rates have remained stable over the past few decades, despite an explosion in mobile phone use during this time. On the other hand, cancers can take a long time to develop after causative exposure begins, so we may be in for a rude awakening in years to come.

In all likelihood, you probably have as much chance of contracting cancer from your phone as from coffee, synthetic lights or peanut butter – all of which have been linked to cancer at one point or another. Nevertheless, it can’t hurt to play it safe.

Switching your phone to flight mode disables the RF transmitter. This means that the phone no longer attempts to establish a network connection which reduces the amount of radiation it emits. However, you’re still going to be exposed to lower frequency magnetic fields while the phone is switched on; especially if you re-enable Wi-Fi.

Another downside to this method is that your app might not actually work in flight mode. These days, it’s not uncommon for mobile applications to require an always-on connection. This is especially true of apps that need to pull data from the cloud and auto-update on the fly. It might be worth researching the app first to determine whether it’s fit to purpose.

On a final note, you’re probably better off keeping your phone out of your bed regardless. As we’ve reported in the past, using electronic devices immediately before sleeping is generally a bad idea as the bright screen inhibits the production of melatonin and hampers the sleeping process — which is precisely what you’re trying to avoid.

A better bet would be a fitness band with an inbuilt sleep tracker. You can read our roundup of the most popular models here. If any readers have tips or suggestions of their own, let SU know in the comments section below.

Cheers Lifehacker

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  • Mobile phones emit non-ionising radiation. That is like radio signals, microwaves and heat, among other things, and very different from ionising radiation like ultraviolet light, radioactivity etc. If non-ionising radiation is strong enough, it will heat and even cook cells in your body, for instance if you are a sailor on a ship and you stand in front of a radar array. But that would be a monstrous amount of energy compared with a mobile phone. The strength of radiation from a phone might just possibly be putting your cells at risk, but there is so much more radiation bombarding your body that the risk is effectively zero. You will receive far more radiation from the sun, nearby powerplants, very big rocks, and pretty much everything else in the universe than your phone. You will also be much more heavily affected by your diet, stress levels, habits, genetics and exercise than by your little mobile friend. Don’t stop being concerned about radiation, but don’t worry about your phone.

  • If I were you, I’d be more concerned about the phone overheating and the battery exploding / smouldering under your pillow rather than RF-EMF giving you brain cancer.

  • The quality of phones as sleep monitors is doubtful anyway. The fitness bands are more accurate (as they are strapped to your body), but even they are not perfect – I used one for a while (until it died) and it reckoned I was fast asleep when I know I was wide awake but lying very still.

  • I wanna ask some questions.
    How many times need in order to cause Brain CA and others.
    Because I bring and use cell phone before I sleep when I was 16.
    Now my age is nearly 18.
    That can cause CA to me?
    if so, what should I do?
    Now i know, I wouldn’t bring cell phone when I sleep.
    Thanks all. ( By the way sorry for my wrong grammar ).

  • I use said sleep cycle app and it doesn’t need WiFi so air plane mode is totally fine. Also cell phone waves aren’t all so bad, better use for you to worry about charging your phone while having it under your pillow because that can cause a fire. Also about blur light, there are many apps out there that can disable or lower the blue light your screen emits. So you could use this app and it probably wouldn’t harm you

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