Long-chain omega-3 fatty acid intake is associated positively with corticolimbic gray matter volume in healthy adults.

Department of Psychiatry, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15260, United States. conklinSM@UPMC.Edu

BACKGROUND: In animals, dendritic arborization and levels of brain derived neurotrophic factor are positively associated with intake of the omega-3 fatty acids. Here, we test whether omega-3 fatty acid intake in humans varies with individual differences in gray matter volume, an in vivo, systems-level index of neuronal integrity. METHODS: Fifty-five healthy adults completed two 24h dietary recall interviews. Intake of long-chain omega-3 fatty acids was categorized by tertiles. Regional gray matter volumes in a putative emotional brain circuitry comprised of the anterior cingulate cortex (ACC), amygdala and hippocampus were calculated using optimized voxel-based morphometry on high-resolution structural magnetic resonance images. RESULTS: Region of interest analyses revealed positive associations between reported dietary omega-3 intake and gray matter volume in the subgenual ACC, the right hippocampus and the right amygdala, adjusted for total gray matter volume of brain. Unconstrained whole-brain analyses confirmed that higher intake of omega-3 fatty acids was selectively associated with increased greater gray matter volume in these and not other regions. CONCLUSIONS: Higher reported consumption of the long-chain omega-3 fatty acids is associated with greater gray matter volume in nodes of a corticolimbic circuitry supporting emotional arousal and regulation. Such associations may mediate previously observed effects of omega-3 fatty acids on memory, mood and affect regulation.

PMID: 17574755 [PubMed - indexed for MEDLINE]