A new study says that Friday the 13th is the only day people suffer from paraskevidekatriaphobia, which is the morbid, irrational fear of the date.
Whether or not a person is superstitious, it's safe to assume people will likely dodge black cats and ladders on that day, just in case the urban legends are true.
"It's in our nature to do what other people in our environment do. If we see that other people are concerned about certain events, we tend to become concerned as well," Britta Ostermeyer from the Baylor College of Medicine, said.
Fear is the normal response to genuine danger. Meanwhile a phobia is a type of anxiety disorder - a strong, excessive, irrational fear of something that poses little or no actual danger.
"A phobia is a mental disorder that causes enormous anxiety and distress for a person. It essentially interferes with a person's life - disturbing daily functions," Ostermeyer adds.
The American Psychiatric Institute for Research and Education estimates 7.8 percent of American adults have phobias. They are the most common psychiatric illnesses among women of all ages and are the second most common among men older than 25.
Phobias may cause a person to avoid common places, circumstances or objects even though they logically know there isn't any danger. In fact, the person might even panic at the idea of coming in contact with the source of the phobia.