A mood disorder affects or interferes with an individual’s emotional state. Someone with a mood disorder may feel sad, happy, or irritable for a long period of time. The two most common mental disorders of mood are depression and bipolar disorder.

Depression affects 17.3 million U.S. people. Depressed individuals can feel sadness, grief, hopelessness, and emptiness without any apparent cause. A traumatic event can also trigger feelings of depression.

Mood Disorders: More Than Feeling Blue

Types of depression include the following:

  • Postpartum depression occurs in new mothers during or after pregnancy.
  • Persistent depressive disorder is chronic and lasts for at least two years.
  • Seasonal affective disorder occurs during certain seasons, usually around winter.
  • Psychotic depression is severe, and episodes can include delusions or hallucinations.
  • Depression related to substance abuse, a medical condition, or medication.

Bipolar disorder includes periods of depression and mania. Mania is when someone feels elated, irritable, or energetic. Those with a type of bipolar disorder can cycle through these feelings regularly. 

More than 3 million people in the country are diagnosed with a type of bipolar disorder. Types of bipolar disorder include the following:

  • Bipolar I is the most severe form and can require hospitalization. Depressive and manic periods can last for seven or more days and even weeks. 
  • Bipolar II causes similar depressive episodes as bipolar I, but the manic periods are less intense. This lower form of mania is called hypomania. 
  • Cyclothymia is a milder type of bipolar disorder with moderate depressive and hypomania periods. However, those with cyclothymia cycle through these moods more quickly.Some psychological issues affect individuals’ relationship with food, which can cause serious health issues.