Vitamin B may not reduce memory loss risk
12th November 2014 - Suggestions that vitamin B12 and folic acid supplements may reduce the risk of memory and thinking problems may not be true after all, according to new research from the Netherlands.
The study published in the online issue of Neurology, the medical journal of the American Academy of Neurology, is one of the largest to date to test long-term use of supplements and thinking and memory skills.
The study involved elderly Dutch men and women with high blood levels of the amino acid homocysteine. High levels of homocysteine have been linked to memory loss and Alzheimer’s disease.
Early observational studies showed there may be some benefit to thinking and memory skills in taking folic acid (vitamin B9) and vitamin B12, but the results of later randomised, controlled trials were less convincing.
Author of the latest study, Dr Rosalie Dhonukshe-Rutten of Wageningen University in the Netherlands, says in a press release: "Since homocysteine levels can be lowered with folic acid and vitamin B12 supplements, the hope has been that taking these vitamins could also reduce the risk of memory loss and Alzheimer’s disease."
However, the new study appears to show that is not the case.
For the current study, 2,919 people with an average age of 74 took either a tablet with 400 μg of folic acid and 500 μg of vitamin B12 or a placebo (dummy pill) every day for 2 years. Tests of memory and thinking skills were performed at the beginning and end of the study. All of the participants had high blood levels of homocysteine.
Rosalie Dhonukshe-Rutten says: "While the homocysteine levels decreased by more in the group taking the B vitamins than in the group taking the placebo, unfortunately there was no difference between the two groups in the scores on the thinking and memory tests."
The authors of the study also note that participants in the B-vitamin group reported cancer more often than those in the placebo group. They say that although the finding could be attributed to chance it should be interpreted with care "and it makes daily supplementation with folic acid in the given dose questionable".
Reacting to the study in a statement, Dr Eric Karran, director of research at Alzheimer’s Research UK says: "This large trial adds to previous evidence suggesting that while vitamin B supplements can lower homocysteine levels, this does not translate into improved memory and thinking in the general older population.
"While some previous studies have suggested that high-dose vitamin B supplements could influence brain changes in people with early memory problems, this trial did not look at people who were already experiencing memory decline. Longer follow-up periods would be needed to see whether vitamin B12 or folic acid supplements could slow the more severe memory decline associated with dementia.
"Although this study casts doubt on the use of vitamin B supplements to aid memory, a balanced diet is a good way to keep healthy at all ages. Evidence suggests that we can maintain a healthy brain for longer by keeping a healthy weight, eating a balanced diet, not smoking, staying active, drinking in moderation and keeping blood pressure and cholesterol in check."