B Vitamins and the Brain: Mechanisms, Dose and Efficacy
Kennedy DO
Published in Nutrients
Abstract
Comprehensive review of B vitamins' effects on brain function, including mechanisms and evidence from clinical trials.
Methodology
Narrative review of the physiological roles of the eight B vitamins in brain function alongside human intervention trial evidence on cognition and mood.
Key Findings
All eight B vitamins have interdependent roles in cerebral energy metabolism, methylation and neurotransmitter synthesis. Marginal deficiency is common, particularly in older adults, and benefits of supplementation are most evident where intake or status is inadequate. Many trials used single vitamins at doses too low, or in populations too well-nourished, to detect an effect.
Conclusions
B vitamins should be considered as an interdependent group rather than in isolation; supplementation is most defensible for correcting suboptimal status rather than for enhancing cognition in well-nourished people.
Limitations
Narrative rather than systematic review with no quantitative pooling or formal risk-of-bias assessment; conclusions rely on heterogeneous trials with differing doses and populations.
Supplements Studied
The B vitamins function as coenzymes in a vast array of catabolic and anabolic enzymatic reactions, and their collective effects are particularly prevalent to numerous aspects of brain function.
Outcomes Measured
The B vitamins function as coenzymes in a vast array of catabolic and anabolic enzymatic reactions underpinning cellular energy metabolism.
The collective effects of the B vitamins are particularly prevalent to numerous aspects of brain function.
Related Health Concerns
Study Details
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This information is for educational purposes only. Always consult a healthcare professional before starting any supplement regimen.