Even at their highest intensity, symptoms of mood disorders are often misinterpreted as merely mood swings. Worse, they are sometimes considered personality flaws rather than real medical conditions. The truth is that mood disorders are treatable medical illnesses caused by a complex interaction of genetic, biochemical and environmental factors.

There are several types of mood disorders: major depressive disorder (unipolar depression); dysthymia; bipolar disorder (also known as manic depression) and cyclothymia.

Depression is one of the most common mental health problems, and is characterized by feelings of sadness or despair that last for at least two weeks and often impair a person's ability to carry out their normal responsibilities in life. Dysthymia resembles depression but has a longer duration. Bipolar disorder is characterized by alternating cycles of lows (depression) and highs (mania or hypomania). Cyclothymia is marked by cycles of low-level depression and hypomania (which is typically shorter in length and less severe than mania).

While the onset of these disorders can occur at any point, most individuals experience their first episode between the ages of 25 and 40.

It is important that mood disorders be accurately diagnosed and treated, as they can take an enormous toll on a person's ability to work, sustain relationships and perform day-to-day activities. Proper treatment not only helps improve the symptoms of these disorders, but can also restore a better quality of life.