Mood disorders can affect people at any life stage. An individual suffering from mood disorder can experience a variety of symptoms that may include fatigue, difficulty concentrating, change in appetite, irritability, agitation, withdrawal, insomnia or excessive sleeping. The causes of mood disorder are still unknown, but it is thought that imbalances in neurotransmitters or chemicals in the brain contribute to symptoms. Several pharmaceutical agents can be used to manage mood disorders, however, many of them have unwanted, negative side effects. Fish oil, and more specifically EPA, has been extensively researched for the role it can play in the promotion of healthy mood balance.