Fish Oil Fails To Treat Alzheimer’s

A recent study from Oregon Health and Sciences University casts doubt on whether fish oil may help patients with Alzheimer's Disease. For 18 months, patients with the illness where given either 2 grams a day of docosahexaenoic acid (DHA, an omega-3 fatty acid found in fish oil) or a placebo. Those who received the DHA did no better in cognitive tests than the placebo group, and MRI scans showed no improvement in brain atrophy either. These results were recently published in the Journal of the American Medical Association. While Joseph Quinn, leader of the study, admits in the paper to JAMA that there are limitations to the conclusions that can be drawn from his experiment, his work seriously challenges those who hoped that fish oil could have a restorative effect on those with Alzheimer's. Sadly, it looks like fish oil has failed us...again.

Fish oil, which contains omega-3 fatty acids which seem key to mental and physical health, has long been thought to have some potential to combat degenerative mental diseases. Alzheimer's Disease forms amyloid plaque on the brain, and tests with transgenic mice who have Alzheimer's have shown that fatty acid supplements can have a preventative and even curative effect for those with plaque buildup. At the same time we know that most humans don't get as much fatty acid as used in experimental conditions, so it seemed natural to believe that relatively strong doses of DHA could have as yet unseen positive effects on people with the disease. This recent failure with human models is disappointing as it suggests that humans don't seem to be affected in the same way as the mice, and that there may be little benefit (to Alzheimer's patients) of upping their DHA intake.

But wait, you say, is this experiment really so cut and dry? Didn't Quinn admit that his test isn't a death knell for fish oil, just a mark against it? Good points, my vocal and imaginary reader. Indeed, the study at Oregon HSU had its limitations. First was its brevity - 18 months is a decent length of time for a nutritional/drug study but perhaps DHA takes longer to reduce plaque buildup on the brain and improve cognition scores. Likewise, this test can only really deny that DHA may work as a curative agent for Alzheimer's. Prevention is still up in the air. The average age for the patients was 76 - maybe we need to focus on younger people who are at high risk for Alzheimer's. Perhaps DHA is only going to delay the onset and severity of the disease.