Research has shown that a deficiency of serotonin in the body can lead to depression, by affecting the general mood of a person.

There are three ways in which the imbalance of serotonin in the body can occur:
* When there is low production of serotonin in the brain
* Failure to receive this neurotransmitter by the parties brain
* The lack of production of tryptophan, a chemical that is responsible for the production of serotonin

Any of these events can lead to an imbalance in serotonin levels in the body, with one result, with depression, along with the anxiety and anger. One of the reasons for these imbalances to occur has been identified as the stress. The stress has the ability to alter a lot of bodily functions, and lack of production of serotonin is known to be one of them.

Serotonin levels in the brain can not be measured by tests, however, have shown that taking antidepressants have been known to induce production of serotonin and therefore lead to a general elevation of mood and relieving symptoms depression different.

However, it is possible to measure serotonin levels in the blood, and has noticed these levels are lower in people who suffer from depression. Thus, although the etiology of depression is not only related to this chemical imbalance, we can deduce that ultimately, the low levels of serotonin have an effect on our mood and therefore depression.