Major depression and atypical depression have been strongly linked to obesity in a number of recent studies. It remains unclear whether depression causes weight gain or weight gain causes depression or the two disorders are linked to an underlying common cause. Since depression and weight gain are both associated with feelings of low self esteem, guilt, shame and hopelessness, it is reasonable to argue that perhaps, for some people, they truly are joint manifestations of a common illness. At present, all that can be said with certainty is that many (but by no means all) people who are depressed gain weight and conversely,overweight people are more likely to be depressed.
What IS Depression?
Like most psychiatric disorders, depression is an illness diagnosed and characterized mostly by subjective symptoms and not by objective laboratory tests or physical signs. This lack of "hard" findings has led many people to question the validity of the diagnosis, but the features of depression, subjective though they are, are highly distinctive and clustered. They include an inability to derive pleasure from and a lack of interest in activities and events that used to be fun, feelings of low self-esteem, difficulty with concentration, memory loss, poor sleep, particularly a pattern of repeated nocturnal waking that lasts hours, feelings of exhaustion, hopelessness and often obsession with thoughts of death, self-harm and suicide. Depression can last for months or years and can occur just once in a person's life, or repeatedly and can occur as a result of personal loss like death or for no apparent reason.
The root causes of depression remain unknown but the illness clearly is related to changes in brain chemistry and function that may either be triggered by external psychological trauma or may occur spontaneoulsy.
Depression can be treated in several ways. Psychotherapy (talk therapy) clearly improves depressive symptoms and so do anti-depressant medications, particularly "selective serotonin re-uptake inhibitors"-(SSRI's) like Prozac. Psychotherapy in combination with antidepressant medication works better than either therapy alone but neither therapy alone or in combination is effective in all cases. Severe depression that fails to respond to these modalities and that puts a person at high risk for suicide is still sometimes treated with "elctroconvulsive therapy"- (ECT)- performed under general anesthesia and this can be effective when all other approaches have failed.
Untreated depression usually (but not always) resolves on its own eventually but places a huge burden upon patients and family members of patients during the time it remains active.