Taking high-dose vitamin B6 tablets helps to reduce feelings of anxiety and depression, new research has shown.
Young adults taking a dose 50 times the recommended daily allowance reported feeling less anxious and depressed after a month.
Vitamin B6 helps the body turn protein and carbohydrates into energy and it also plays important role in the nervous system.
It is also known to increase the body’s production of GABA (Gamma-Aminobutyric Acid), a chemical that blocks impulses between nerve cells in the brain.
It is found naturally in a variety of foods from salmon and tuna to chickpeas and bananas.
Dr David Field of the University of Reading and lead author of the study said: “The functioning of the brain relies on a delicate balance between the excitatory neurons that carry information around and inhibitory ones, which prevent runaway activity.
“Recent theories have connected mood disorders and some other neuropsychiatric conditions with a disturbance of this balance, often in the direction of raised levels of brain activity.
“Vitamin B6 helps the body produce a specific chemical messenger that inhibits impulses in the brain, and our study links this calming effect with reduced anxiety among the participants.”
The study, published in the journal Human Psychopharmacology: Clinical and Experimental, provides evidence lacking in previous studies as to what exactly drives the stress-reducing effects of marmite and multivitamins.
More than 300 participants were randomly assigned either a placebo or Vitamin B6 or B12 supplements at 50 times the recommended amount – around 70mg – and took one tablet a day with food.
Vitamin B12 had little effect compared to the placebo but B6 showed a statistically reliable difference.
Visual tests at the end of the trial confirmed the raised levels of GABA in participants who had taken Vitamin B6, supporting the hypothesis that the supplements were reducing anxiety.
Subtle but harmless changes in visual performance were detected, consistent with controlled levels of brain activity.
The NHS recommends that people do not take too high a dose – more than 200mg a day – as it can lead to a loss of feeling in the arms and legs, adding that in a few cases this has become permanent in people who have taken very large doses for several months.
Dr Field said: “Many foods, including tuna, chickpeas and many fruits and vegetables, contain Vitamin B6. However, the high doses used in this trial suggest that supplements would be necessary to have a positive effect on mood.
“It is important to acknowledge that this research is at an early stage and the effect of Vitamin B6 on anxiety in our study was quite small compared to what you would expect from medication.
“However, nutrition-based interventions produce far fewer unpleasant side effects than drugs, and so in the future people might prefer them as an intervention.
“To make this a realistic choice, further research is needed to identify other nutrition-based interventions that benefit mental wellbeing, allowing different dietary interventions to be combined in future to provide greater results.
“One potential option would be to combine Vitamin B6 supplements with talking therapies such as Cognitive Behavioral Therapy to boost their effect.”