A recent study at The British Institute of Psychiatry showed that checking your email while performing another creative task decreases your IQ in the moment 10 points. That is the equivalent of not sleeping for 36 hours—more than twice the impact of smoking marijuana.
Found this interesting and a little scary. Although you may think that you are more effective checking your email, eating lunch, talking on the phone, taking care of kids or pets, and so much more, they all have an impact. And that is actually costing you money.
So take time to breathe, do one thing at a time, and then bask at how this increases your productivity and effectiveness.