Mainstream psychiatry reinstates therapeutic ventures of the remote past.

The reinstatement and revision of abandoned therapeutic ventures of the past has been an integral part of medical research and advancement. In psychiatry, much interest was generated recently by emerging data on the use of faecal supplements for restoring the neurochemical balance in the brain, and on the ingestion of placenta to stabilize neural circuits disrupted by childbirth-related hormonal changes. Herein, we consider the emerging scientific evidence and socio-cultural prerequisites favouring the re-entry of these heterodox customs, which are reminiscent of widespread instinctive behaviours in wildlife, into modern healthcare. We explore their evolutionary background and adaptive significance, and consider mechanisms of therapeutic benefits. Finally, we reflect on emerging opportunities and challenges, which present clues towards better prevention and treatment of major neuropsychiatric disorders.