Recent research shows that eating fish and other foods rich in omega-3 fatty acids could help people maintain healthy brains as they age, as well as protect their hearts. The study involved 1,575 participants with an average age of 67 who did not suffer from dementia, a condition typically marked by memory loss. The study appears in the February issue of the Journal Neurology.
The leading author of this work is Dr. Zaldy Tan, a researcher at the University of California, Los Angeles (UCLA). Participants with low levels of omega-3 fatty acids in their blood had slightly smaller brains and scored lower on memory and cognitive tests than people with higher blood levels of omega-3s. These differences were maintained even after factoring in a number of variables such as age, gender, education, body mass index, smoking and the APOE genotype.
Several studies have shown diets that include fish, such as the Mediterranean diet, lower the incidence of heart problems or heart attacks. And some studies suggest that the intake of fatty fish like salmon and tuna may lower the risk of Alzheimer’s disease and other causes of dementia.
However not all studies have found such an association for Alzheimer’s disease. One reason for this inconsistency may be related to most diet studies relying on food-frequency questionnaires to determine dietary intake, which might not reflect accurately what is consumed over a certain time period. The study led by Dr. Tan measured the level of omega-3 fatty acids in red blood cells over three months.
The researchers then looked at and ranked the level of omega-3 fatty acids in the blood of the participants taking part in the study. People who scored in the bottom 25% in omega-3 fatty acid levels were compared with the rest of the participants in the study. Researchers found that those who had the lowest level of omega-3 fatty acid levels in their blood had lower brain volume compared with those with higher levels. They also scored lower on several tests such as problem solving, multi-tasking and abstract thinking.