IH. Campbell, N. Needham, H. Grossi, I. Kamenska, S. Luz, S. Sheehan, G. Thompson, MJ. Thrippleton, MC. Gibbs, J. Leitao, T. Moses, K. Burgess, BP. Rigby, SA. Simpson, E. McIntosh, R. Brown, B. Meadowcroft, F. Creasy, M. Mitchell-Grigorjeva, J. Norrie, A. McLellan, C. Fisher, T. Zieliński, G. Gaggioni, H. Campbell, et al. (2025). A pilot study of a ketogenic diet in bipolar disorder: clinical, metabolic and magnetic resonance spectroscopy findings. BJPsych open, 11(2), e34. https://doi.org/10.1192/bjo.2024.841

PubMed 39995103

[Abstract]
BACKGROUND: Preliminary evidence suggests that a ketogenic diet may be effective for bipolar disorder.

AIMS: To assess the impact of a ketogenic diet in bipolar disorder on clinical, metabolic and magnetic resonance spectroscopy outcomes.

METHOD: Euthymic individuals with bipolar disorder (N = 27) were recruited to a 6- to 8-week single-arm open pilot study of a modified ketogenic diet. Clinical, metabolic and MRS measures were assessed before and after the intervention.

RESULTS: Of 27 recruited participants, 26 began and 20 completed the ketogenic diet. For participants completing the intervention, mean body weight fell by 4.2 kg (P < 0.001), mean body mass index fell by 1.5 kg/m2 (P < 0.001) and mean systolic blood pressure fell by 7.4 mmHg (P < 0.041). The euthymic participants had average baseline and follow-up assessments consistent with them being in the euthymic range with no statistically significant changes in Affective Lability Scale-18, Beck Depression Inventory and Young Mania Rating Scale. In participants providing reliable daily ecological momentary assessment data (n = 14), there was a positive correlation between daily ketone levels and self-rated mood (r = 0.21, P < 0.001) and energy (r = 0.19 P < 0.001), and an inverse correlation between ketone levels and both impulsivity (r = -0.30, P < 0.001) and anxiety (r = -0.19, P < 0.001). From the MRS measurements, brain glutamate plus glutamine concentration decreased by 11.6% in the anterior cingulate cortex (P = 0.025) and fell by 13.6% in the posterior cingulate cortex (P = <0.001).

CONCLUSIONS: These findings suggest that a ketogenic diet may be clinically useful in bipolar disorder, for both mental health and metabolic outcomes. Replication and randomised controlled trials are now warranted.