Fish May Protect Brain From Effects of Aging
Fatty Fish May Help Prevent Alzheimer's, but Other Fats Raise Risks
Jan. 26, 2004 -- Fish really may be brain food after all. A new
study shows the omega-3 fatty acids found in fish can help fight the effects of
aging on the brain and may reduce the risk of Alzheimer's disease.
But other types of saturated fats that raise cholesterol levels
may actually increase the risk of age-related declines in mental
The study showed that middle-aged men and women who ate a lot
of fatty fish, such as tuna and salmon, were less likely to suffer from
declines in mental performance. But those who had a high-fat diet had a higher
risk of these declines.
Researchers say subtle declines in mental performance can be
found at middle age, years before more serious symptoms of Alzheimer's
Omega-3 Fatty Acids Protect the Brain
Researchers say few studies have looked at the relationship
between eating fish and mental performance, especially in middle-aged people.
The study, published in the January issue of Neurology, looks at the
effects of fatty acid and fish consumption on mental performance in a group of
1,613 men and women aged 45 to 70.
The participants went through extensive mental performance
testing, including tests that assessed their memory, thought processing speed,
and mental flexibility, in order to pick up mild declines in brain function,
and filled out questionnaires about their diet.
Researchers found that the participants' risk of mental decline
was decreased for those who ate more fatty fish.
Specifically, the risk of impaired brain function and
processing speed decreased by 19% and 28% for every increase in the amount of
omega-3 polyunsaturated fatty acids they ate.
Cholesterol Raises Brain Risks
But when researchers looked at overall fat and saturated fat
intake, they found a significant association between an increased risk of
impairment and higher intakes of fat and cholesterol in the diet.
For example, the risk of impairment in memory, speed, and
flexibility increased by 15% to 19% for each increase in saturated fat the
The risk of impaired memory and flexibility also increased by
27% and 26%, respectively, for each increase in the amount of dietary
cholesterol in the diet.
Researchers say eating more fish has already been shown to
reduce the risk of heart disease, and the next step will be to determine if
those dietary changes might actually help prevent age-related diseases of the
brain, such as dementia and Alzheimer's disease.