Docosahexaenoic acid

DHA is an appealing PUFA (poly-unsaturated fatty acid) delivered by fish oil. French investigators theorize that this PUFA or omega-3 fatty acid becomes incorporated into the cell membranes of neurons. Once embedded in the cellular surface, DHA may protect against the injurious effects of amyloid-beta, the protein fragment that gums up the brainworks in Alzheimer's disease.

And in clinical news, a decade long study of Boston oldsters showed a 48% decrease in the incidence of AD among those who had the highest levels of DHA due to regular intake of fatty fish.