Researchers from Oxford University report their two-year clinical trial was the largest to date regarding the treatment of mild cognitive impairment with B vitamins. The scientists conducted a study with 168 volunteers with mild cognitive impairement who were given either a vitamin pill containing high doses of folic acid, vitamin B6 and vitamin B12, or a placebo dummy pill. Brain scans were taken at the beginning and the end of the trial to monitor the rate of brain shrinkage. On average the brains of those taking the vitamins shrank at a rate of 0.76 percent a year, while those taking the dummy pill had an average brain shrinkage of 1.08 percent.
  
     Comments:
Over the years there have been conflicting reports regarding the use of B vitamins in seniors as a way to reduce the progression of brain atrophy with age. Overall, though, the balance points to some benefits and I don't see any harm in taking a low to moderate dose of a B complex supplement a few times a week. An alternative is to take a capsule or two of MultiVit Rx which has all the B vitamins along with several other antioxidants and minerals. Another option is to take a capsule of Mind Power Rx a few times a week. The study used only three vitamins, folic acid, B6, and B12. It is possible that the other B vitamins could also be of benefit. The ideal dosage of these vitamins for long term use, such as several years or decades, is not known. Therefore, to be on the safe side, I would suggest taking an amount lower than what they used in the trial.

See http://www.raysahelian.com/dementia.html for more information.