An Omega-3 fatty acid called docosahexenoic acid, or DHA for short, can help people with mild memory problems but not those with full-blown Alzheimer's disease. Researchers from Oregon Health and Sciences University in Portland carried out two studies of DHA. The first compared it to a placebo in 402 people with mild-moderate Alzheimer's and found no change in people's symptoms. The second study, of 485 healthy older adults with mild memory problems, looked at the effectiveness of a 900mg daily dose of DHA and found that it boosted learning and memory skills to the level of someone three years younger.
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