While you are sleeping, as your body repairs and regenerates, as your brain sorts and files memories, why not do yourself a favour and turn off your WiFi?
It’s questionable whether EMF radiation is having a lifetime impact on your health, but why not buy a timer for Â£5 from Wilko, Argos or Homebase and set it to go off automatically from 11pm until 7am (and engage airplane mode on your phone as well if you have it next to you in the bedroom).
There’s very little actual data showing even basic correlation of smartphone and WiFi use causing cancer or tumours, because it’s thought that the frequencies used (being lower even than visible light) passes through us harmlessly and we’ve now had 20 years of data to research the effects.
Also use a blue filter if you read your smartphone in bed, many smartphones now come with “comfort mode” viewing buit in these days but if not download an app.
If you want to go the whole hog you should use your smartphone at least 1 inch away from your ear, or use a headphone cable, and get an EMF liner for your bag which blocks harmful radiation.