“Depression is caused by a simple chemical imbalance in the brain.”
Strong confidence. A systematic umbrella review found no consistent support for depression being caused by low serotonin, and modern clinical models treat depression as heterogeneous and multifactorial. Antidepressant efficacy does not establish a simple deficiency model.
Depression is not explained by one simple shortage or imbalance of serotonin. It can involve interacting biological, psychological and social factors, and different people may reach similar symptoms through different pathways.
A treatment can work without correcting the original cause. Antidepressants can help some people, but their benefit does not prove that depression began as a serotonin deficiency.
Safety note: Rejecting the chemical-imbalance slogan does not mean depression is imaginary or that medication should be stopped. Abruptly stopping an antidepressant can cause withdrawal symptoms and relapse risk.
Talk to a healthcare professional if: Discuss treatment changes with the prescriber. Seek urgent help for suicidal thoughts, inability to stay safe, severe agitation, mania, psychosis or rapidly worsening symptoms.
You do not need a one-chemical explanation for your symptoms to be real or treatable.
Use a shared treatment plan based on symptoms, severity, preferences and response, and review medication decisions with a qualified clinician.
Similar claims on Antidepressants (SSRIs)
The old 'chemical imbalance' line was an oversimplification - but that doesn't mean antidepressants don't help, and for many they clearly do. This is a decision to make with a clinician, not internet debates.