The results of a new study headed by Oxford University showed that vitamins B6, B12, and folic acid reduced brain atrophy, improved brain function, and dramatically reduced brain shrinkage in the part of the brain most affected in Alzheimer's. (1) Study participants took 800 mcg of folic acid, 20 mg of B6, and 500 mcg of B12 over a 2-year period. The image below shows brain scans from the control group and the group that took B vitamins. The placebo image shows much more brain atrophy (areas in yellow) than the vitamin B group.