Fatty fish includes salmonoften eaten with
bagelsalong with lake trout, herring and sardines.
For information on balancing the
risks and benefits of seafood choices, visit this
National Academies Press
website and click "Read this book online."
Can Fish Intake Predict Chances of Developing
Dementia? By Rosalie Marion Bliss
November 14, 2006
People who ate the most fish on a weekly basisputting them in
the top quarter of a study populationwere nearly 50 percent less likely
to develop the mental deterioration known as dementia over time than
participants in any of the other three quarters.
The observational study was led by
J. Schaefer, an Agricultural Research Service-funded scientist.
ARS is the U.S. Department of Agriculture's chief
scientific research agency. Schaefer is a physician specializing in nutrition
and health with the
Mayer USDA Human Nutrition Research Center on Aging at
Tufts University in Boston, Mass.
He and co-authors were looking for a relationship between blood levels
of the fatty acid DHA and the risk of developing dementia. DHA is short for
docosahexaenoic acid, a so-called "heart-healthy" omega-3 fatty acid. Several
different studies have linked either low DHA, or low fish intake levels, with
the incidence of dementia.
The study was published in the November 13 issue of the Archives of Neurology. Schaefer
and colleagues analyzed available dietary questionnaires and blood levels of
DHA of nearly 900 men and women, aged 55 to 88, who participated in the
longitudinal Framingham (Mass.)
At the beginning of a nine-year period, all of the participants were
found to be free of dementia. Using proportional regression analysis, the
researchers determined the relative impact not only of blood levels of DHA, but
also of potential "confounding" variables such as age, gender, homocysteine and
apolipoprotein-E levels, genotype and education.
They found that the participants who reported consuming an average of
about three servings of oily fish a weekequivalent to blood levels of DHA
at 180 milligrams dailywere associated with a significantly reduced risk
of developing dementia of all types, including Alzheimer's disease. No other
fatty acid blood level was independently linked to the risk of dementia.
The study suggests that relatively higher fish consumption over time
correlates with a lower incidence of dementia in the over-55 set.