Cause and Effect

Research has established a link between depression and an imbalance of chemical messengers in the brain. Heredity also plays a role, though not everyone who has a strong family history of the disorder will develop it. Personality type is a factor, with those who are pessimistic and easily stressed more likely to become depressed. Stressful events, such as death of a loved one or a change in living arrangements or finances, can trigger depression. But it also may occur for no apparent reason.

Depression can take a tremendous toll both on sufferers and on those who love and care for them. People who are depressed can feel wiped out—exhausted and helpless. Such negative feelings may cause sufferers to feel like giving up. It's important that they don't. These feelings are part of the illness that is depression, and they will fade as treatment begins to take effect.