Depression is one of the most common problems my patients face. Whether it is generated by some personal life events, or general ones (such as the Covid-19 pandemic, the economic crisis etc.), one thing is certain: the number of people suffering from depression is constantly increasing.
For years it has been thought that low serotonin (the hormone of happiness) in humans is the main reason why depression can take over the body. Whether serotonin is synthesized little, or it is quickly destroyed, or the receptors that should respond to it do not work well – one way or another, it all comes down to increasing its level in neurons and interneuronal connections-synapses; this is how most antidepressants work (or at least should work).
However, the new study of British researchers speaks of the failure of the "serotonin theory". In an article in Molecular Psychiatry, they mention that there is no conclusive evidence that serotonin has anything to do with depression.
This statement is based on a comparative review of other studies as well as meta-analyses on serotonin and depression. The researchers reviewed 17 studies that analyzed serotonin levels in thousands of people, both healthy and depressed. As a result, the researchers came to the conclusion that there is no evidence that depression occurs due to a lack of the "hormone of happiness."
In addition, artificially lowering the level of serotonin in healthy volunteers also did not lead to the development of depression in them.
Another very large study, which involved tens of thousands of patients, studied the variability of genes, including the gene for the serotonin transporter. In the review, the researchers found no differences in these genes between people with depression and healthy people.
The scientists say their findings are important because studies show that 85 to 90 percent of the population believe depression is caused by low levels of serotonin or a ”chemical imbalance” in the brain.
According to lead author of the study, psychiatrist Professor Joanna Moncrieff, the popularity of the "chemical imbalance" theory coincides with the increase in the use of antidepressants: “Many people take antidepressants because they have been led to believe their depression has a biochemical cause, but this new research suggests this belief is not grounded in evidence.”
There is also evidence that the belief that bad mood is caused by a chemical imbalance in the brain leads to a pessimistic view of the likelihood of recovery and the ability to cope with mood swings without medical attention. This is important because most people meet criteria for anxiety or depression at some point in their lives.
Experts say patients shouldn't be told that depression is caused by low levels of serotonin or a chemical imbalance in the brain. Moreover, patients should not be convinced that antidepressants will help them recover, as it is not yet known how they act on the brain. Misinformation can influence a patient's decision to take or not take antidepressants.
Recently, more and more specialists consider that the presentation of depression as a purely chemical problem is an oversimplification of the situation. The authors of the article themselves believe that their results will help change the idea of depression, the causes of which can be not only in “chemical imbalances”, but also in constant stress, loneliness and poverty.
Since there is evidence that stressful events strongly influence the risk of depression, the researchers suggest encouraging other coping strategies such as psychotherapy sessions, mindfulness techniques, physical activity, etc.
For my part, I suggest people suffering from depression not to forget about the miraculous power of nature. While experts will study the effects of antidepressants, you can safely turn to natural anti-stress remedies.