Bipolar disorder and major depression are associated with significant disability, morbidity, and reduced
life expectancy. People with mood disorders have shown higher ratios of unhealthy lifestyle choices, including
poor diet quality and suboptimal nutrition. Diet and nutrition impact on brain /mental health, but cognitive
outcomes have been less researched in psychiatric disorders. Neurocognitive dysfunction is a major driver of
social dysfunction and a therapeutic target in mood disorders, although effective cognitive-enhancers are currently
lacking. This narrative review aimed to assess the potential cognitive benefits of dietary and nutritional
interventions in subjects diagnosed with mood disorders. Eight clinical trials with nutrients were identified,
whereas none involved dietary interventions. Efficacy to improve select cognitive deficits has been reported, but
results are either preliminary or inconsistent. Methodological recommendations for future cognition trials in the
field are advanced. Current evidence and future views are discussed from the perspectives of precision medicine,
clinical staging, nutritional psychiatry, and the brain-gut-microbiota axis.