It's not always possible to prevent depression. But preventing depression is not the only way to avoid the kind of impact a depressive episode can have on your life. You can minimize the effect of depression by learning to recognize the signs and symptoms of depression. Then you can alert your health care provider and get depression treatment when it's most helpful.

What is depression?

Depression is a condition that is defined by at least five of the following nine symptoms being present at the same time for at least two weeks in adults or one week in children or adolescents:

a depressed mood during most of the day, particularly in the morning
fatigue or loss of energy almost every day
feelings of worthlessness or guilt almost every day
impaired concentration, indecisiveness
insomnia or hypersomnia (excessive sleeping) almost every day
markedly diminished interest or pleasure in almost all activities nearly every day -- a condition called anhedonia that can be indicated by a subjective account or by observations of significant others
recurring thoughts of death or suicide (not just fearing death)
a sense of restlessness -- known as psychomotor agitation -- or being slowed down -- retardation
significant weight loss or gain (a change of more than 5% of body weight in a month)

How can I prevent depression?

Although depression is a highly treatable condition, some forms of depression may not be preventable. That's because depression may be triggered by a chemical malfunctioning in the brain. However, the latest medical studies confirm that depression may often be alleviated or sometimes prevented with good health habits.

Proper diet, exercise, taking time out for fun and relaxation, not overworking, and saving time to do things you enjoy may work together to prevent a depressed mood.

What are some of the common feelings associated with depression?

The National Institute of Mental Health identifies a number of common symptoms experienced by people with depression:

difficulty concentrating, remembering details, and making decisions
fatigue and decreased energy
feelings of guilt, worthlessness, and/or helplessness
feelings of hopelessness and/or pessimism
insomnia, early-morning wakefulness, or excessive sleeping
irritability, restlessness
loss of interest in activities or hobbies once pleasurable, including sex
overeating or appetite loss
persistent aches or pains, headaches, cramps, or digestive problems that do not ease even with treatment
persistent sad, anxious, or "empty" feelings
thoughts of suicide, suicide attempts

While these are common symptoms of depression, they may also occur in patterns. For example, a person may experience depression with mania or hypomania -- a condition sometimes called manic depression or bipolar disorder. Or the symptoms may be seasonal as in the case of seasonal affective disorder.

There are several types of manic depression. People with bipolar II disorder have at least one episode of major depression and at least one hypomanic -- mild elation or high -- episode. People with bipolar I disorder have a history of at least one manic -- extreme elation or high -- episode, with or without past major depressive episodes. A patient with unipolar depression has major depression only but does not have hypomania or mania.