You may throw on an outfit without much thought in the morning, but your choice is strongly affected by your mood. And the item of casual wear in almost everyone's wardrobe -- denim jeans -- is what most people wear when depressed, new research from psychologists at the University of Hertfordshire reveals.

A study conducted by Professor Karen Pine, co-author of "Flex: Do Something Different, found that what a woman chooses to wear is heavily dependent upon her emotional state."* One hundred women were asked what they wore when feeling depressed and more than half of them said jeans. Only a third would wear jeans when feeling happy. In a low mood a woman is also much more likely to wear a baggy top; 57% of the women said they would wear a baggy top when depressed, yet a mere 2% would wear one when feeling happy. Women also revealed they would be ten times more likely to put on a favorite dress when happy (62%) than when depressed (6%).

The psychologists conclude that the strong link between clothing and mood state suggests we should put on clothes that we associate with happiness, even when feeling low.

Professor Pine said: "This finding shows that clothing doesn't just influence others, it reflects and influences the wearer's mood too. Many of the women in this study felt they could alter their mood by changing what they wore. This demonstrates the psychological power of clothing and how the right choices could influence a person's happiness."

Accessories can make a difference too. The study found that:

    •Twice as many women said they would wear a hat when happy than when depressed.
    •Five times as many women said they would wear their favorite shoes when happy (31%) than when depressed (6%).

The study found that 'happy' clothes -- ones that made women feel good -- were well-cut, figure enhancing, and made from bright and beautiful fabrics. Professor Pine pointed out that these are exactly the features that jeans lack: "Jeans don't look great on everyone. They are often poorly cut and badly fitting. Jeans can signal that the wearer hasn't bothered with their appearance. People who are depressed often lose interest in how they look and don't wish to stand out, so the correlation between depression and wearing jeans is understandable. Most importantly, this research suggests that we can dress for happiness, but that might mean ditching the jeans."

*FLEX: Do Something Different. How to use the other 9/10ths of your personality, by psychologists Professor Ben (C) Fletcher and Professor Karen Pine, published January 2012 by University of Hertfordshire Press.