The recent medical study, conducted by researchers from University College London, contradicted the old medical opinions that depression is due to an imbalance of serotonin in the brain.
Serotonin is a neurotransmitter that plays a key role in controlling mood, sleep, digestion, and a number of other bodily functions.
The study, published in the journal Molecular Psychiatry, concluded that there is no clear evidence that serotonin levels or activity are responsible for depression.
For years, chemical imbalances of serotonin were widely seen as the cause of depression, leading to the widespread use of antidepressants such as selective serotonin reuptake inhibitors.
The study’s lead author, Professor Joanna Moncrieff, said there was no convincing evidence that depression was caused by a “serotonin abnormality”.
The study included research that compared levels of serotonin and its breakdown products in blood or brain fluids and found no significant difference between those diagnosed with depression and healthy participants.
The researchers also evaluated studies in which hundreds of participants’ serotonin levels were artificially reduced by deleting the amino acids needed to make it from their diets.
They found that artificially lowering serotonin did not result in depression in the study volunteers.
The research highlights the need to find new treatment methods for depression, especially since there are several factors that cause it, and they affect people in different ways.
Commenting on the study, APA chief scientific officer Mitch Bernstein said, “There is no one-size-fits-all treatment approach for people with depression.”
Major depression is one of the most common mental disorders in the United States, affecting more than 8 percent of Americans.