Can Omega-3 Fatty Acids Prevent Alzheimer's Disease?

Alzheimer's dementia is the disease most Americans fear most - and for good reason. This relentlessly progressive brain condition robs a person of their retirement years and families of the people they love. No wonder there's so much interest in preventing Alzheimer's disease. One preventative treatment that holds promise for prevention of Alzheimer's disease, at least for a portion of the population. are the omega-3 fatty acids in fatty fish.

Omega-3 and Alzheimer's Dementia

Researchers recently discovered that a diet high in omega-3 fatty acids and low in cholesterol helps to offset the effects of a gene that puts people at high risk for Alzheimer's disease. This gene called APOE is mutated in about 15% of the population to a "bad" form called APOE4 that raises the risk of Alzheimer's. About half of all people with Alzheimer's dementia have this gene.

Using a mouse model, researchers at Tel Aviv University used animal models to test the effects diet would on the APOE4 gene. In mice, they found that a diet rich in omega-3 fatty acids and low in cholesterol offset the effects of this gene that predisposes to Alzheimer's dementia. Could an omega-3 rich diet prevent Alzheimer's disease in humans too?

Omega-3s to Prevent Alzheimer's Disease?

Whether or not omega-3s counteract the effects of this gene in humans too is still unknown. Omega-3 supplements proved disappointing in a recent study that looked at whether they slow down the progression of Alzheimer's disease.

This study, published in the Journal of the American Medical Association, clearly showed that giving DHA, an omega-3 fatty acid, to people with Alzheimer's disease didn't reduce the rate of progression of Alzheimer's disease. On the other hand, the study was short, the dose of DHA was low and they didn't include the other important omega-3, EPA, in the study.

On the bright side, this study did show a slight benefit of taking omega-3s for people with the APOE-4 gene.

Omega-3 and Alzheimer's Disease: The Bottom Line?

The omega-3s in fish oil could be useful for preventing Alzheimer's dementia in a certain percentage of the population who has the APOE-4 gene that puts them at high risk for Alzheimer's disease. This doesn't necessarily mean fish oils will benefit everyone at risk for the disease since there are other gene types that predispose a person to Alzheimer's disease.

On the other hand, omega-3 fatty acids reduce inflammation and are heart-healthy, so there are few drawbacks to taking fish oil supplements. The exception would be people who have bleeding disorders or who are on a blood thinner. Talk to your doctor about whether omega-3 fatty acids are right for you, especially if you have a family history of Alzheimer's disease.

References:

Medical News Today. "Diets High in Fish Oil Have a Beneficial Effect in Patients at Risk of Alzheimer's"