OPAL (Older People And omega-3 Long-chain polyunsaturated fatty acids)
Over 2 years, researchers from the UK and Australia followed almost 900 septuagenarians for any benefits on cognition from omega-3 supplementation.
First, the details.
- 867 cognitively healthy adults were randomly assigned a treatment group for 2 years.
- Omega-3: 200 mg eicosapentaenoic acid (EPA) + 500 mg docosahexaenoic acid (DHA) daily
- Olive oil
- A trained research nurse administered a battery of cognitive tests, including the California Verbal Learning Test (CVLT).
- The results were adjusted for cognitive (test of reasoning) scores, age, gender, and age at leaving full-time education.
- Neither the patients nor researchers knew the treatment given — double blind.
And, the results.
- Average blood levels of EPA and DHA were significantly higher in the omega-3 group vs placebo at 24 months (50 mg vs 39 mg EPA/L and 96 mg vs 71mg DHA/L, respectively).
- There was no change in cognitive function in either group at 24 months.
The bottom line?
The authors acknowledge that the lack of cognitive decline in the control group (olive oil) and the relatively brief treatment may have limited the ability to detect any beneficial effect of fish oil on cognitive function.
Also, it’s possible that the omega-3 group was treated with an insufficient dose. And I’m not sure it was a good idea to use olive oil as a control, considering it might have some benefits on it’s own.
Another confounding factor might be the life choices these participants followed during their first 60 years of life.
4/24/10 19:46 JR