What role do hormones play in mental health complaints, and does current psychiatry fall short by only targeting symptoms?

Cortisol, the body's primary stress hormone, clearly plays a role in a proportion of mental health complaints. In people with severe depression, the so-called HPA axis (the system that produces cortisol) is frequently dysregulated. Reviews support this association in a substantial subgroup, but not in all depressed patients. This makes it impossible to view depression as a single hormonal disorder.

The strongest evidence for direct hormonal causality comes from Cushing's syndrome, a condition in which the adrenal gland structurally produces too much cortisol. Patients genuinely develop psychiatric and cognitive complaints. This is an indication that high cortisol levels do not merely accompany mental health problems but can also trigger them.

A meta-analysis of 80 studies shows that people with a flatter cortisol curve across the day have, on average, poorer mental and physical health. The association is small to moderate, and whether the abnormal cortisol curve is a cause or a consequence has not been established.

Chronically elevated stress hormones damage brain structures involved in memory and emotion regulation. Early traumatic experiences, such as abuse or neglect in childhood, demonstrably increase this long-term risk. There is also a clear association with low socioeconomic status.

The question of whether psychiatry falls short by targeting only symptoms receives some support from HPA axis research. Reviews describe that certain drugs targeting the cortisol system show promising results in patients with demonstrable HPA axis abnormalities. Tests that measure those abnormalities could, in theory, help select the right treatment. However, this approach is not yet standard in clinical practice, and the evidence remains limited to early-stage studies.