Summary: The prevalence of vitamin B12 in Marmite may increase levels of GABA in the brain, a new study reports.
Source: University of York.
Scientists at the University of York have discovered a potential link between eating Marmite and activity in the brain, through the apparent increase of a chemical messenger associated with healthy brain function.
Participants consuming a teaspoon of Marmite every day for a month, compared to a control group who consumed peanut butter, showed a substantial reduction of around 30 per cent in their brain’s response to visual stimuli, measured by recording electrical activity using electroencephalography (EEG).
Researchers think this may be due to the prevalence of vitamin B12 in Marmite increasing levels of a specific neurotransmitter – known as GABA – in the brain.
GABA inhibits the excitability of neurons in the brain, with the chemical acting to ‘turn down the volume’ of neural responses in order to regulate the delicate balance of activity needed to maintain a healthy brain.
As Marmite consumption appears to increase GABA levels, this study is the first to show that dietary intervention may affect these neural processes. GABA imbalances are also associated with a variety of neurological disorders.
Anika Smith, PhD student in York’s Department of Psychology and first author of the study, said: “These results suggest that dietary choices can affect the cortical processes of excitation and inhibition – consistent with increased levels of GABA – that are vital in maintaining a healthy brain.
“As the effects of Marmite consumption took around eight weeks to wear off after participants stopped the study, this suggests that dietary changes could potentially have long-term effects on brain function.
“This is a really promising first example of how dietary interventions can alter cortical processes, and a great starting point for exploring whether a more refined version of this technique could have some medical or therapeutic applications in the future. Of course, further research is needed to confirm and investigate this, but the study is an excellent basis for this.”
Dr Daniel Baker, Lecturer in the Department of Psychology and senior author of the paper, said: “The high concentration of Vitamin B12 in Marmite is likely to be the primary factor behind results showing a significant reduction in participants’ responsiveness to visual stimuli.
“Since we’ve found a connection between diet and specific brain processes involving GABA, this research paves the way for further studies looking into how diet could be used as a potential route to understanding this neurotransmitter.
“Although GABA is involved in various diseases we can make no therapeutic recommendations based on these results, and individuals with a medical condition should always seek treatment from their GP.”
Funding: This research was supported by the American Federation for Aging Research.
Source: Saskia Angenent – University of York
Image Source: NeuroscienceNews.com image is credited to WestportWiki and is licensed CC BY-SA 3.0.
Original Research: Abstract for “Dietary modulation of cortical excitation and inhibition” by Anika K Smith, Alex R Wade, Kirsty EH Penkman, and Daniel H Baker Journal of Psychopharmacology. Published online April 4 2017 doi:10.1177/0269881117699613
Dietary modulation of cortical excitation and inhibition
The balance of excitatory and inhibitory neurotransmitters in the brain affects both neural responses and behaviour in humans and animals. Here we investigated whether dietary intervention aimed at increasing levels of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) can influence neural responses to basic sensory stimuli. Using a steady-state electroencephalography (EEG) paradigm, we found that the neural response to visual patterns was reduced in individuals who consumed a yeast extract product rich in substances associated with the production of GABA (glutamate and B vitamins), but not in a control group who consumed a placebo substance (n = 14 per group). This demonstrates that the balance of excitation and inhibition in the brain can be influenced by dietary interventions, suggesting possible clinical benefits in conditions (e.g. epilepsy) where inhibition is abnormal.
“Dietary modulation of cortical excitation and inhibition” by Anika K Smith, Alex R Wade, Kirsty EH Penkman, and Daniel H Baker Journal of Psychopharmacology. Published online April 4 2017 doi:10.1177/0269881117699613