What is the relationship between vitamins and cognitive health? Should we take vitamin supplements to increase our brain functions? What is the evidence? A recent study, published in the journal Neurology, indicates that low levels of vitamins B12 may be associated with low cognitive scores and brain volume.
The study involved 121 people age 65 and older whose blood was drawn to measure levels of vitamin B12 and B12-related metabolites that can indicate a B12 deficiency. Four and a half years later on average, the participants’ brains were scanned to both measure their total brain volume and look for any signs of brain damage. The participants’ memory and other cognitive skills were also assessed at that time.
The results of the study showed that having high levels of four of five markers for vitamin B12 deficiency was associated with lower scores on the cognitive tests and a smaller total brain volume.
What does it mean?
First of all, note that the level of vitamin B12 itself in the blood was not associated with cognitive problems or loss in brain volume. Only biological markers of vitamin B12 deficiency were. So it is not easy to assess whether someone is deficient in vitamin B12, especially when looking only at the level of vitamin B12 itself.
Second, it is not because B12 deficiency is associated with lower cognitive skills that increasing levels of B12 through diet or supplements could increase cognitive skills. There is no evidence for this yet. Moreover, the causes of cognitive decline are probably too complex to be halted with a single vitamin supplement.
To date, no supplement has been shown to effectively slow down cognitive decline and postpone Alzheimer’s disease symptoms. It seems that there is no magic pill to brain health and no single solution. Your best bet so far is a brain-healthy lifestyle including at least physical exercise, balanced diet, mental stimulation and brain training, stress management, and social engagement.
Tangney et al. (2011). Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology, 77:1276-1282.
Learn more about the link between diet/supplements and cognitive health here: