Vitamin B12 deficiency can lead to significant problems in the nervous system including muscle weakness, problems with walking, tiredness, and pins and needles, as well as depression and problems with memory. Vitamin B12 is found in everyday foods such as fish, meat, poultry and dairy products.
"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," said Alan Dangour, reader in Food and Nutrition for Global Health at London School of Hygiene & Tropical Medicine.
The effects of daily supplementation with vitamin B12 to correct moderate deficiency on nervous system function were previously unknown. Researchers conducted a trial of 201 people aged over 75 years. Participants, who had moderate vitamin B12 deficiency and were not anaemic, received a tablet every day for one year containing either vitamin B12 or a placebo.
At the end of the study after 12 months of supplementation, participants undertook clinical tests to assess their nervous system function.
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.
"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," Dangour said.
The study appeared in the American Journal of Clinical Nutrition.
