What is the definition of clinical depression?

Changes in weight and appetite can be symptoms of clinical depression, says Jeffrey Borenstein, MD, a psychiatrist at The Brain and Behavior Research Foundation. He elaborates on the most telling signs of depression.

Learn how the symptoms of depression differ from everyday sadness—plus, strategies to feel better.

Temporary lifts in mood, overeating, and hypersomnia may be signs of this subtype of major depressive disorder.

Seasonal affective disorder can occur in the spring and summer as well as the fall and winter.

Learn what increases the odds that you or a loved one will experience major depressive disorder.

Learn how to feel energized after lunch—without coffee.