More support for omega-3 to slow age-related cognitive decline

Researchers at Martek Biosciences Corporation, in Columbia, Maryland, studied the effects of docosahexaenoic acid (DHA) (an essential fatty acid) on improving cognitive functions in healthy older adults with age-related cognitive decline.

First, the details.

• 485 healthy adults had a Mini-Mental State Examination score greater than 26 and a Logical Memory (Wechsler Memory Scale III) baseline score at least 1 standard deviation below younger adults.
  • In other words, they had subjective memory complaints and mild memory deficit, but no dementia.
  • A Mini-Mental State Examination score below 20 usually indicates cognitive (reasoning) impairment.
  • Wechsler Memory Scale III is designed to assess learning, memory, and working memory.
• They were randomly assigned to a treatment group for 24 weeks.
  • 900 mg/day of DHA taken by mouth
  • Matching placebo
• The researchers looked for changes in the CANTAB Paired Associate Learning (PAL), which assesses visual memory and new learning.
• Neither the patients nor researchers knew the treatment given — double blind.

And, the results.

• Participants taking DHA supplements made significantly fewer errors in visual memory and new learning, but there was no difference between groups.
• DHA supplementation was also associated with significantly improved immediate and delayed verbal recognition memory scores, but not working memory or executive function tests.

The bottom line?

The authors concluded, “24-week supplementation with 900 mg/d DHA improved learning and memory function in ARCD and is a beneficial supplement that supports cognitive health with aging.”

It’s modest improvement, and supports the conclusions in an earlier review of 15 studies. “The existing data favor a role for long-chain omega-3 fatty acids in slowing cognitive decline in elderly individuals without dementia, but not for the prevention or treatment of dementia (including Alzheimer’s disease).”

11/27/10 16:50 JR