Maybe we'll all be issued with black out curtains! Or prescribed melatonin. Or both. But then the article says more research on timing of taking tamox and melatonin is needed.
Does it also mean phone chargers and pc's lights at night?
What about if you need to get up in the night, or you're a shift worker?
I hope this is just a case of correlation = causation and nothing more. I'm paranoid enough as it is! Taking tamox is bad enough without the added possibility that light at night stops it working..