(Cleveland) - For some people, Friday the 13th is not just like any other day. Experts say more than 20-million people are afraid of this so-called “unlucky” day.

Dr. Scott Bea is a clinical psychologist at Cleveland Clinic. He says there are a lot of reasons people fear Friday the 13th, but it starts with superstition.

“People who are anxious or fearful of Friday the 13th are just not going to tempt fate. They’d rather avoid than risk it, and here’s the other thing that happens, if something bad does happen on Friday the 13th it quickly gets assigned that it happened on Friday the 13th,” says Dr. Bea.

Dr. Bea says superstitions begin when two events that are unrelated get connected somehow and then endorsed by other people.

The “unluckiness” of the number 13 goes way back, even to the Last Supper where Judas was the thirteenth and last guest invited.

Friday was also “hanging” day in the 17th century, so that may be where the connection is made.

In any case, people will avoid flying on Friday the 13th, not many homes are bought on this day, and you won’t find too many “Friday the 13th” wedding anniversaries.

Dr. Bea says you should not let your fear get the best of you. A good way to overcome it is to face it head-on.

“Write the number 13 on a piece of paper stick it in your pocket and walk around all day with it. That would actually endorse your fearlessness in the face of that fear rather than trying to play it safe,” says Dr. Bea.

On the flip side, if you consider Friday the 13th, or the number 13 lucky, you’re probably more of a risk-taker or thrill-seeker. You’ll also tend to trust in yourself rather than the superstition.

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