Review: B vitamins, the brain (& deficiencies)

A proportion of populations, particularly in developing countries, suffer from deficiencies or in one or more B vitamins.

Studies​ ​have found 40% of school-aged children in Kenya were low in plasma vitamin B12 concentrations. Similar results were found in Zimbabwe (24% of the elderly), Israel (21% in adults), and India(46% in adults).

Study details​

In congress, Dr David Kennedy, director of the Brain, Performance and Nutrition Research Centre at Northumbria University, presented a review of the B vitamin family.

His aim was to gather evidence that proved a certain level of all eight B vitamins are required in order to achieve optimal brain and body function.

Additional findings demonstrated the effects on brain function following four weeks use of a neurotropic multivitamin supplement.

Kennedy concluded that in the absence of an optimal diet, administration of the entire B vitamin group, at doses in excess of current governmental recommendations, would be a rational approach for preserving brain health.

“Whilst adequate levels of all of the B vitamins should be obtainable from a healthy diet, deficiencies or marginal deficiencies in one or more B vitamins will predispose these populations to a number of negative health consequences, including less than optimal brain function,”​ said Dr Kennedy.

“It is therefore difficult to conceive of any potential downsides to undertaking research with the full range of B vitamins."​

B vitamins​

The B vitamin family consists of thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), vitamin B6, biotin (B7), folate (B9) and vitamin B12).

Given their physiological significance, trial research efforts in this area have concentrated mainly on the small sub-set of B vitamins (folate, vitamin B12 and, to a lesser extent vitamin B6) that play the most obvious roles in amino acid metabolism.

The roles of the remaining five B vitamins have been largely overlooked and possibly as a result of this, studies that have involved administering just folic acid, vitamins B12 and/or B6, have generated results that are open to more than one interpretation.

Multi-vitamin studies ‘inevitable’​

While Dr Kennedy believed research with the full range of B vitamins was the next step, he commented that the luxury of being able to attribute any benefits to a single molecule and/or a single mechanism would be lost.

“However, given the equivocal nature of the large body of evidence to date, this loss would appear supportable, if not inevitable.”​

A recent study​​ investigated the impact of two doses of multi-vitamins/minerals. It demonstrated increased fat metabolism and overall energy expenditure during cognitive task performance within two hours of consuming the higher dose (3 times Recommended Dietary Allowance (RDA)) of water soluble vitamins, and increased cerebral blood-flow following the lower 1 x RDA dose of vitamins.

Another study​​ investigated the effects of a multivitamin/mineral on cognitive function in children after a single dose (and after four and eight weeks) and found improvements in attention task performance and in a semantic memory task were evident as early as three hours following the first dose.

Also speaking at the event was Dr Andrew Scholey, director of the Centre for Human Psychopharmacology at Swinburne University in Australia.

He outlined the results of a four-week assessment on neurotropic multi-vitamins supplementation that was associated with improvements in mood​​ and functional brain activity.

With his team, Scholey mapped brain activity using two technologies – Steady State Topography and Functional Magnetic Resonance imaging. Both technologies were able to demonstrate increased activation in parietal-frontal brain regions associated with attention and working memory.

Source: Human Psychopharmacology​

Published online ahead of print, doi:10.3390/nu8020068​​

"B Vitamins and the Brain: Mechanisms, Dose and Efficacy—A Review”​

Authors: David Kennedy