Vitamin B12 supplements offer no benefits for neurological or cognitive function in older people with moderate vitamin B12 deficiency, according to UK study funded by the government.
The authors of the study, published in the American Journal of Clinical Nutrition, noted that around one sixth of people in the UK aged over 75 have vitamin B12 deficiency.
Previous studies have suggested that people with moderate vitamin B12 deficiency have poorer nerve and memory functions.
However, the effects of daily supplementation with vitamin B12 to correct moderate deficiency on nervous system function were previously unknown, according to the authors of the new study.
“Our study found no evidence of benefit for nervous system or cognitive function from 12 months of supplementation”
They conducted a trial of 201 people aged over 75, who had moderate vitamin B12 deficiency. They received a tablet every day for one year containing vitamin B12 or a placebo.
After 12 months, participants undertook clinical tests to assess their nervous system function including measures of muscle strength, coordination, mobility, tests of cognitive function including memory, and of psychological health.
The researchers found no evidence of improved neurological or cognitive function among people who received vitamin B12 compared to those who received the placebo tablets.
The researchers stated that the supplements contained a safe, recommended dose of vitamin B12.
But they noted it was possible that the dose may have been too low to affect neurological or cognitive function, or that the supplements might be needed for several years to have an impact.
Lead author Dr Alan Dangour, from the London School of Hygiene and Tropical Medicine, said: “This is the first trial of the effect of vitamin B12 supplementation on neurological and cognitive function in older people with moderate vitamin B12 deficiency.
“Our study found no evidence of benefit for nervous system or cognitive function from 12 months of supplementation among older people with moderate vitamin B12 deficiency,” he said.
He added: “We advise older people concerned about their health and cognitive function to eat a diverse and healthy diet, keep cognitively active and when possible take regular physical activity.”
The study was conducted by a team of researchers from the London School of Hygiene and Tropical Medicine, King’s College London, University College London, and Oxford University.
The study was funded by the Department of Health and the nutrition team at the Food Standards Agency which is now part of Public Health England.