fish oil and
BRAIN HEALTH
A ROCKEFELLER UNIVERSITY REPORT
__________________________________
Many
people take fish oil supplements for heart health, and there
is some research to suggest that fish oils may be good for the
brain as well. Now researchers have shown that fish oil supplements
may affect parts of the brain critical for memory and thinking
skills.
For
the study, scientists at Rhode Island Hospital's Alzheimer's
Disease and Memory Disorders Center studied 819 men and women,
117 of whom were taking fish oil supplements. All were part
of the Alzheimer's Disease Neuroimaging Initiative, a large
and ongoing study at multiple medical centers across the country.
The participants were given memory tests at the start of the
study, and periodically over the next three years. Their brains
were also scanned as part of the study.
The
researchers found that among those who were healthy at the study's
start, those who were taking fish oil supplements scored higher,
over all, on tests of memory and thinking than those who were
not taking fish oils. Fish oils seemed to provide benefits for
those who did not carry a gene called APOE-E4, which increases
the risk for Alzheimer's disease.
In
addition, the brains of those taking fish oils were larger than
those who were not taking the supplements, particularly in two
brain structures critical for memory and thinking: the hippocampus
and the cerebral cortex. A larger brain is generally a sign
of better cognitive health; conversely, brain shrinkage has
been associated with Alzheimer's disease. Again, the brain benefits
applied only to those who did not carry the APOE-E4 gene.
The
findings, reported at the International Conference on Alzheimer's
Disease in Paris, "should motivate further study of the
possible effects of long-term fish oil supplementation on important
markers of cognitive decline and the potential influence of
genetics on these outcomes," said Dr. Lori Daiello, who
led the study.
Other
studies have shown that a diet rich in fish, particularly oily
fish like tuna, salmon, mackerel, sardines and anchovies, may
lower the risk of Alzheimer's disease and other forms of dementia.
Studies of people who eat a traditional Mediterranean diet rich
in fish as well as fruits and vegetables, for example, have
shown that the diet may have brain-protective effects. Another
survey of seniors in Asia, Latin American and the Caribbean
found that those who ate fish almost every day were almost 20
percent less likely to develop dementia than those who ate fish
a few days a week. Eating fish may also help to ease the agitation
and depression of Alzheimer’s, other research shows.
Fish
oils contain omega-3 fatty acids like DHA, or docosahexaenoic
acid, which is known to be good for cardiovascular health. People
with high levels of DHA in their bodies had a lower risk of
developing Alzheimer's disease in one large study. Researchers
speculate that the omega-3s in fish oil may quell inflammation,
which is emerging as a possible underlying cause of heart disease
and other ills, including Alzheimer’s disease.
Fish
oil supplements containing DHA and other omega-3s are widely
available in pharmacies and health-food stores. But more study
is needed to better define the effects of diet on brain health.
Advancing age, family history and genes like APOE-E4, as this
study indicates, can all influence the risk for Alzheimer's
disease.
By
alzinfo.org, Fisher
Center for Alzheimer's Research Foundation at The Rockefeller
University.