Today is the day for people who suffer from paraskevidekatriaphobia to try to keep their cool — but it won’t be easy. Why? The condition is a deep, blinding fear of Friday the 13th. And however irrational the fear may seem, it has some concrete consequences.

The year 2012 is an especially bad year for those who fear this day. Most years have one or two Friday the 13ths, but this year, there are three. And get this: They are 13 weeks apart. (January 13th, April 13th, July 13th).

It has been estimated that up to $800 million is lost every Friday the 13th because many people think it is an unlucky day to travel, go to work or do pretty much anything. In fact, it is said that as many as 21 million people fear this day.

And according to this Daily Mail article, a 1993 study in the United States found that the risk of admission to hospitals on Friday the 13th as a result of “a transport accident may be increased by as much as 52 percent.” The study was detailed in an article that was called “Is Friday 13th bad for your health?” and published in the British Medical Journal.

So how did Friday the 13th become such a day of fear to so many people for no scientific reason? It depends on who you ask.

Donald Dossey, founder of the Stress Management Center and Phobia Institute in North Carolina, was quoted by National Geographic as saying the Friday the 13th fear can be tracked by to a Norse myth about a dinner in Valhalla, Norse heaven. Twelve gods were invited but a 13th crashed the affair and wreaked havoc, thus tarnishing the number 13th ever after.

Thomas Fernsler, a math specialist at the University of Delaware, says people fear Friday the 13th for different reasons, according to the school’s Web site.

Thirteen, he says on the site, “suffers from its position after 12, which numerologists consider a complete number, encompassing the number of months in a year, signs of the zodiac, gods of Olympus, labors of Hercules, tribes of Israel, apostles of Jesus, days of Christmas and eggs in a dozen.”

According to Fernsler, lots of people fear the number 13 — a condition called triskaidekaphobia — and have throughout history, including Napoleon, J. Paul Getty, Herbert Hoover and Franklin D. Roosevelt.

Here are some other “13 facts” from Fernsler:

*The ill-fated Apollo 13 launched at 13:13 CST on 4/11/70. The sum of the date’s digits is 13. The explosion that crippled the spacecraft occurred on April 13.
*President Franklin D. Roosevelt would not travel on the 13th day of any month and would never host 13 guests at a meal.

According to, Mark Twain once was the 13th guest at a dinner party that a friend warned him to avoid. “It was bad luck,” Twain later told the friend. “They only had food for 12.” In fact, in Paris, the site said, superstitious diners “can hire a quatorzieme, or professional 14th guest.”

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