The mind/body connection

Metabolic psychiatry is a subspecialty focused on targeting metabolic dysfunction to improve mental health

Legatees of René Descartes (1596–1650) might deprecate Ventriglio and Bhugra’s paper in Epidemiology and Psychiatric Sciences (2015, 24: 368–370) contending that Cartesian mind–body dualism has created major problems for Western medicine and Western psychiatry. Dumping Descartes’ dogma, they argue, entails recognising “that mind-body dualism is false. The mind affects the body and the body affects the mind.” This statement, as the French Revolution established, confirms the importance of the neck in human affairs.

Further proof of the neck’s significance at the interface of metabolism and mental illness is furnished by Ir J Psychol Med (2024, 41: 418–419) where Usman et al report on ‘Establishing a dedicated metabolic clinic for patients with chronic mental illness’ in Sligo/Leitrim, and in Eur J Psych (2011, 25: 213–222) where O’Callaghan et al describe ‘Screening for metabolic syndrome in long-term psychiatric illness: Audit of patients receiving depot antipsychotic medication at a [Dublin] psychiatry clinic’.

Metabolic psychiatry, coined by Stanford University’s Dr Shebani Sethi, is “a new subspecialty focused on targeting and treating metabolic dysfunction to improve mental health outcomes”. Only weeks ago, a £7.9 million randomised controlled trial (RCT) got underway, with Edinburgh and Birmingham universities comparing how a very-low-carbohydrate, high-fat ketogenic diet versus the NHS-recommended Eatwell diet affects depressive symptoms in people with bipolar disorder (BD).

Dr Iain Campbell is Baszucki Research Fellow in Metabolic Psychiatry at the University of Edinburgh, Scotland. In an interview, Dr Campbell told me: “As a patient-researcher living with BD, this trial is a huge win for both the patient community and metabolic psychiatry. I had depressive episodes at primary school; hypomania at high school; and over a decade later was diagnosed with BD.”

Before Campbell’s career in neuroscience began, music was the only means by which he could live with BD.

“During hypomanias, for brief periods creativity and productivity would flow effortlessly, and music helped communicate my experience. During the depressions I would grind to a halt, unable to function, but I’d still have the songs I created when I was up.”

Aged 21, Campbell was signed to Island Records as recording artist Kid Adrift; in 2010 his band played Glastonbury; and today he and his wife compose cinematic music as Ex Makina, their music having featured on the recent BBC Traitors series.

Despite the relatively recent interest in metabolic psychiatry, the first report of a ketogenic diet to treat mental illness was in 1965, when Abel Pacheco – later President of Costa Rica from 2002 to 2006 – and colleagues reported in Am J Psych (1965, 121: 1110–1111) on “A pilot study of the ketogenic diet in schizophrenia” where 10 hospitalised women placed on a ketogenic diet for a fortnight showed significant improvement.

And in their retrospective analysis of patients with treatment-refractory mental illness, Danan et al, in Front Psychiatry (2022, 13:951376) not only reported on the feasibility of a ketogenic diet, which was associated with “substantial improvements in depression and psychosis symptoms and multiple markers of metabolic health”, but speculated that the apparent separation between neurological and psychiatric illness may be more rhetorical than biological, given their common origin in the brain; shared biochemical similarities like dysfunctional neurotransmitter systems; unstable neural networks; neuroinflammation; excessive oxidative stress; aberrant neuroplasticity; mitochondrial dysfunction; and disturbed cerebral glucose metabolism.

All of this raises the possibility that some mental illnesses may be the result of brain energy disorders.

So, with a ketogenic diet versus the NHS Eatwell Guide being compared, the outcome of the RCT underway at Edinburgh and Birmingham universities will be awaited with interest.

All of this raises the possibility that some mental illnesses may be the result of brain energy disorders