Kate Sweeny, associate professor of psychology at the University of California, recently analysed the behaviours and mind-sets of frequent worriers – and she found that fretting can encourage behaviours that lead to better health, more success, and greater wellbeing.

Speaking to NBC News Better, she said: “Much like most negative emotions, worry does have a function. We probably wouldn't have evolved to worry if there was no reason to do it.

“When it comes to worry, that function is pretty clear: it draws our attention to the fact that there's something we maybe should be doing or preparing for or preventing, and it gives us the motivation to do something about that.”

Essentially, worrying helps us to prepare for the future – and reminds us to take action. However there is such a thing as worrying too much.

Clinical psychologist Melanie Greenberg explains: “If worry interferes with your life, if you can't focus and concentrate, if it's spoiling your pleasure in life, if you're procrastinating because you're so worried about how things will go, if you're just keyed up all the time and can't relax, if you're worrying about the same thing over and over and you can't put it aside, that would be unproductive.”

Worrying is a sign of high intelligence, according to scientists