In case you’re reading this article in the middle of the night because you can’t fall asleep, you’ve got company.  Globally, insomnia is the world’s most common sleep disorder with 30 % or 2.2 billion people who suffer frequently from it.  When you have persistent sleep problems – at least 3 nights per week - with falling or staying asleep or both and you wake up feeling unrefreshed, this can have a negative impact on your ability to function during the day.