Vitamin B12 May Not Help Everybody

By Jane Farrell

Although taking Vitamin B12 helps older people who have a serious deficiency of the substance, it doesn’t improve neurological or cognitive function in older people with only moderate B12 deficiency, according to a new study.

The research, from investigators at the London School of Hygiene & Tropical Medicine, was published in the American Journal of Clinical Nutrition.

The 201 participants in the study, all of whom were over 75 years old, had moderate vitamin B12 deficiency and were not anemic. They took a tablet every day for one year; it contained either vitamin B12 or a placebo.

At the end of the study, participants underwent clinical tests to evaluate their nervous-system functioning. These tests evaluated muscle strength, coordination, mobility, cognitive function (including memory) and psychological health.

In analyzing the results, 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.

Previous research has shown that people with severe B12 deficiency (with or without anemia) can benefit from treatment with B12. Severe deficiency can lead to 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.

But until this most recent study, the effect of B12 on people who had moderate deficiency were not known.

Dr Alan Dangour, Reader in Food and Nutrition for Global Health at the London School of Hygiene & Tropical Medicine, said: “Many people may be taking vitamin B12 supplements on a regular basis and it has been thought they would enhance function in older people. 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.

“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.”