Do Omega-3 Fats Prevent Dementia?
What did they study?
The Cochrane Collaboration performed the review and published their findings in the Cochrane Database of Systematic Reviews. After looking at all of the studies of omega-3 fats and changes in thinking (cognitive) ability, the researchers found three high-quality trials to review. These trials together included 4,080 healthy people over age 60 who were given supplements providing 400 to 1,800 mg of the omega-3 fats, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), per day or placebo. They were monitored for cognitive change for 6 to 24 months.
What did they find?
The authors summarized: “Omega-3 PUFAs [polyunsaturated fatty acids] were shown to provide no benefit to cognitive function among cognitively healthy older people who took a variety of cognitive tests at baseline and final follow-up, including the Mini-Mental State Examination and tests of memory and executive function.” They also noted that longer trials might yet reveal a benefit from supplementing with omega-3 fats, and encouraged the use of omega-3 fats for their other health benefits.
What does it mean?
Cochrane reviews are considered one of the highest standards for evidence-based practice. They analyze studies with a strict set of criteria, looking for high-quality study methods as well as any potential bias on the part of the researchers. However, the conclusions they reach are very specific: in this case, the finding is that there is not enough evidence at this time to suggest that healthy seniors using omega-3 supplements are protected from cognitive decline.
Whether different amounts of omega-3s might show different effects, whether omega-3 fats prevent dementia over longer periods of time, or whether they may benefit people who already have age-related cognitive decline or dementia still needs to be explored.
What are the study-supported uses of omega-3s?
Although omega-3 fats may not prevent cognitive decline in healthy older people, research has shown that there are several other solid reasons to eat cold-water fish or take omega-3 fatty acid supplements:
- Protect your heart and blood vessels. Omega-3 fats have been found to improve the health and function of blood vessels, help regulate heart rhythm, and protect against sudden cardiac death. In addition, a Cochrane review found adequate evidence to show that replacing saturated with unsaturated fats, such as omega-3 fats, can reduce the risks of heart attack and stroke.
- Ease joint pain. Omega-3 fats can reduce joint pain in people with rheumatoid arthritis and inflammatory bowel disease.
- Manage your mind. Omega-3 fats have been found to help people who suffer from anxiety, depression, and the depressive symptoms that can be part of bipolar disorder.
(Cochrane Database Syst Rev 2012;6:CD005379)