A New Study on Omega-3 Fatty Acid Supplements and Alzheimer's Disease

It has been known for some time that eating fish provides a level of protection from Alzheimer's disease, especially if red meat is eliminated from the diet.  The assumption was that omega-3 fatty acids in the oil in the fish was the protective agent.  Therefore, using fish oil supplements was deemed to be a good protective strategy.  (Omega-3 fatty acids are also found in olive oil and tree nuts, and these too convey a protective effect.)  But innumerable placebo controlled studies failed to support the notion that fish oil itself, separated from the fish, provides protection.  As with some other food-borne agents (like resveratrol), once the agent is separated from the food, the agent loses its protective or healing power.

However, a new study out of Sweden has found some preventative effect from certain omega-3 fatty acid supplements, including limited restoration of cognition in persons with mild symptoms of Alzheimer's disease.  

The study was small, involving only 33 patients, 15 of whom were on the placebo.  Eighteen were given omega-3 fatty acid supplements twice per day for six months.  The researchers looked for changes in mini mental status exam (MMSE) results and changes in biomarkers in cerebrospinal fluid (CSF).  (We discuss the MMSE in Beating the Dementia Monster.)

In a press release, Dr. Yvonne Freund-Levi noted, “We can see that the memory function of the patients in the group that had taken omega-3 is stable, whereas the patients in the control group have deteriorated. That’s what the memory tests show. But we can’t see any differences between the groups when we look at the various biomarkers in the spinal fluid samples.”  So this is kind of a disconnect.  If you see improvement in cognitive test scores, you should also see changes in the CSF.  But they didn't.

Also, the patients that did show improved MMSE scores began from relatively high levels -- maybe higher than mine when I was first diagnosed.  Subjects with lower scores at the beginning did not improve.

They concluded that this points to the need for a larger study, maybe one with 200 subjects.  In the meantime, this study does not provide a basis for changing health recommendations.  According to Dr. Freund-Levi, the existing recommendations are to be physically active and include omega-3 in your diet – in the form of oily fish or as supplement.  Do you remember the Dementia Tool Kit in Beating the Dementia Monster?  If you apply the exercise and diet tools, you're there.