How much time have you wasted worrying about eventualities that never come to pass?

Your brain is ultra-adept at identifying and worrying about potential threats, stresses and dangers, says life and business coach Tony Robbins.

"The way out of suffering is to realize we all have a 2 million-year-old brain. It's not designed to make you happy, it is designed to make you survive. So it's always looking for what's wrong so you can fight it or flight from it or freeze," Robbins tells CNBC Make It. "It overreacts because there isn't a saber-toothed tiger anymore."

In other words, in modern times, your brain usually doesn't have to protect you from imminent danger, so it focuses on other stressors.

"Now you worry about, 'What are people thinking of me?' or, 'Do I have enough money?'" says Robbins. "And the truth of the matter is, fear doesn't make you better."

This understanding of the brain and how fear works led Robbins to develop what he calls his "90-second rule." He says take 90 seconds to do the following:

First, learn to recognize stress by observing when it shows up in your body as tension. Second, carefully identify whether that fear is legitimate. Often it is just your brain's instinct for protection acting out. If the fear is unfounded, the third step is to visualize the stress or anxiety passing through your brain like a fog or a wave.