UCLA scientists are now reporting that fish oil is indeed a deterrent against Alzheimer's, and they have identified the reasons why. This confirms a lot of research that has shown the benefit of omega-3 fatty acids in the prevention of this neurodegenerative disease.
Reporting in the current issue of the Journal of Neuroscience, Dr. Greg Cole (Professor of Medicine and Neurology at UCLA and Associate Director, UCLA's Alzheimer Disease Research Center) and his colleagues report that the omega-3 fatty acid docosahexaenoic acid (DHA) found in fish oil increases the production of a protein (LR11) that is found at reduced levels in Alzheimer's patients and which is known to destroy the "plaques" associated with the disease.
These plaques are deposits of a protein called beta amyloid that is thought to be toxic to neurons in the brain, leading to Alzheimer's. Since having high levels of the LR11 protein prevents the toxic plaques from being made, it is assumed that low levels in patients are a factor in causing the disease.
These researchers examined the effects of fish oil (specifically its component DHA) in multiple biological systems and administered the oil or fatty acid by diet and by adding it directly to neurons grown in the laboratory. They found that even low doses of DHA increased the levels of LR11. Cole said that dietary DHA increased LR11 in brains of rats or older mice that had been genetically altered to develop Alzheimer's disease.
To show that the benefits of DHA were not limited to nonhuman animal cells, the researchers also confirmed a direct impact of DHA on human neuronal cells in culture as well. Thus, high levels of DHA leading to abundant LR11 seem to protect against Alzheimer's, Cole said, while low LR11 levels lead to formation of the amyloid plaques.
Fish oil and its key ingredient, omega-3 fatty acids (found in fatty fish like salmon), have been a mainstay of alternative health practitioners for years and have been endorsed by the American Heart Association to reduce the risk of cardiovascular disease.