Alzheimer's disease and other forms of dementia occur in older adults and cause memory loss, confusion and eventually death. Approximately 4.5 million people now have Alzheimer's disease and the number is expected to rise to about 16 million people by 2050. Omega 3 essential fatty acids found in fish consist of biologically active EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). DHA comprises between 30 to 50 percent of the fatty acid content of the brain. Previous studies suggest that deficiencies in DHA are associated with cognitive impairment. Now research reports that higher levels of DHA may prevent dementia and Alzheimer's disease.
The study, published in Archives of Neurology, investigated whether DHA levels are associated with dementia and Alzheimer disease. Researchers at Tuffs University, in Boston, analyzed the data of 899 seniors with no signs of dementia at the beginning of the study, as part of the Framingham Heart Study. The participants were followed for nine years. Neuropsychological tests, blood samples analyzed for DHA levels, dementia screenings, and dietary questionnaires were obtained from the participants.
Researchers found that 99 participants developed dementia, including 71 participants who developed Alzheimer's. Findings revealed that participants with the highest DHA levels had a 47 percent lower risk of developing dementia and a 39 percent lower risk of Alzheimer's disease, compared to those with lower DHA levels. Participants among the top one-fourth of fish intake, had a mean fish intake of three times a week, with an average of 180 milligrams DHA daily.
"The top quartile of plasma phosphatidylcholine (PC) DHA level was associated with a significant 47% reduction in the risk of developing all-cause dementia in the Framingham Heart Study," the study authors conclude.
REFERENCES:
1. Schaefer EJ et al. Plasma phosphatidylcholine docosahexaenoic acid content and risk of dementia and Alzheimer disease: the Framingham Heart Study. Arch Neurol 2006 Nov;63(11):1545-50.
Posted by Elaine Gavalas on December 12, 2006 03:36 PM
