Depression is a common and serious medical condition that negatively affects the way you feel, think, and behave. Fortunately, it's also treatable. Depression causes feelings of sadness and loss of interest in activities you once enjoyed. It can cause a variety of emotional and physical problems, which can affect your ability to work and at home. 

An estimated 1 in 15 adults (6.7%) suffer from depression each year, and 1 in 6 adults (16.6%) will suffer from depression at some point in their lives. Depression can begin at any time, but on average it first appears in people's late teens to mid-20s. Women suffer from depression more often than men, and some studies have shown that one in three women will experience a major depressive episode during their lifetime.

Symptoms of depression can range from mild to severe and include:

  • Feeling sad or depressed
  • Loss of interest or enjoyment in activities you once enjoyed
  • Changes in appetite (over or under-eating, weight loss or weight gain not caused by a medical condition)
  • Difficulty sleeping or sleeping too much
  • Loss of energy or increased feeling of fatigue
  • Increased nonsensical physical activity or movement (e.g., hand wringing or pacing)
  • Slowed speech (acts that may be observed by others)
  • Feelings of worthlessness or guilt
  • Difficulty thinking, concentrating, or making decisions
  • Thinking of death or suicide

How Is Depression Treated?

Diagnosing depression requires that symptoms must have been present for at least two weeks. Additionally, some medical conditions (such as thyroid disease, brain tumors, and vitamin deficiencies) can mimic the symptoms of depression, so it's important to rule out common medical causes. 

Depression is among the most treatable of mental disorders. Between 80% and 90% of people with depression will eventually respond well to treatment. Almost all patients gain some relief from their symptoms.

Click here to view treatment options.

Depression Is Different From Sadness or Grief/Bereavement

The death of a loved one, the loss of a job, or the end of a relationship is a painful experience. Feelings of sadness and grief are normal in response to these situations. People who have experienced loss often describe themselves as "depressed." But being sad and being depressed is not the same. The grieving process is natural and different for each person, and it may share some of the same characteristics as depression. Both sadness and depression can involve intense sadness and withdrawal from normal activities. They also differ in important ways.

  • During grief, painful emotions come in waves and often mix with positive memories of the deceased. With severe depression, mood and interest (joy) decrease for a majority of 2 weeks.
  • Self-esteem usually remains intact during grief. Severe depression often causes feelings of worthlessness and self-loathing.
  • For some people, the death of a loved one can lead to severe depression. Losing a job or being the victim of physical assault or catastrophe can also lead to this for some people. 

When sadness and depression occur together, the sadness is more severe and lasts longer than sadness without depression. Although there is some overlap between sadness and depression, they are different. Distinguishing between them can help ensure that people receive the help, support, and treatment they need.

Risk Factors for Depression

Depression can affect anyone—even a person who appears to live in relatively ideal circumstances. Several factors can play a role in depression:

  • Biochemistry: Differences in certain chemicals in the brain may contribute to symptoms of depression.
  • Genetics: Depression can run in families. For example, if an identical twin has depression, she has a 70% chance that the other will also develop the disease at some point in her life.
  • Personality: People who have low self-esteem, are easily overwhelmed by stress, or are generally pessimistic seem to be more likely to suffer from depression.
  • Environmental Factors: Constant exposure to violence, neglect, abuse, or poverty can make some people more susceptible to depression