We all have our obsessions: Some cannot stand a dirty floor or some prefer a certain brand of toothbrush and cannot let go.

Well, as long as these obsessions do not interfere with your life there is nothing to worry about, but if they do, it may be a mental disease.

Obsessive-Compulsive Disorder (OCD) is a common, chronic and long-lasting disorder which can make a person have uncontrollable, reoccurring thoughts (obsessions) and behaviors (compulsions) that they feel the urge to repeat over and over again.

According to the U.K.-based research center Understanding Obsessive Compulsive Disorder (UOCD), approximately 2.3 percent of the world population, between ages 18 and 54, suffer from OCD, which far outranks mental disorders such as schizophrenia, bipolar or panic disorder.

In the U.S., approximately 3.3 million people have OCD - about 2 percent of the adult population - the center says.

Obsessions and compulsions can change according to people's backgrounds and culture. Cleaning and control are the things that Turkish people are mostly obsessed with, according to a recent research. Two of every 100 people are obsessed with cleaning in Turkey. It is understandable as Turkey has long placed a cultural and religious premium on cleanliness.

Seventeenth-century French author, traveler, and diplomat Melchisedech Thevenot wrote that Turks frequently visited Turkish baths to clean their body and maintain their health. In the Quran, there are a number of verses which emphasize the importance of cleanliness: "Truly, Allah loves those who turn to Him constantly and He loves those who keep themselves pure and clean."

Apart from cleaning and control, Turkish people are also obsessed about not to say the wrong thing to offend others and placing everything according to a symmetrical or mathematical order.