A new study by UCLA researchers shows that a diet lacking in omega-3 fatty acids, which are commonly found in fish, may cause your brain to age faster and lose some of its memory and thinking capabilities. The research demonstrated that people with lower levels of omega-3 fatty acids have lower brain volumes — equivalent to approximately two years of structural brain aging.
The 1,575 dementia-free study subjects (average age 67) underwent MRI brain scans and were given tests measuring mental function, body mass and omega-3 fatty acid levels in their red blood cells. Omega-3 fatty acids include the nutrients docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Researchers found that those whose DHA levels were in the bottom 25 percent had lower brain volumes than those with higher DHA levels. In addition, those whose levels of all omega-3 fatty acids were in the bottom 25 percent scored lower on tests of visual memory and executive function, including problem-solving, multi-tasking and abstract thinking.
Higher fish intake has been associated with a reduced risk of cardiovascular mortality and stroke. And while some studies have shown an association between eating fatty fish and a lower risk of dementia, others have failed to confirm such a protective association. This study, which focused on middle-aged to elderly subjects who were free of clinical stroke and dementia, confirmed the association.
Dr. Zaldy S. Tan, a member of the Easton Center for Alzheimer's Disease Research in the UCLA Department of Neurology who also holds an appointment in the UCLA Division of Geriatrics, is available for interviews.
The study was supported by the National Heart, Lung, and Blood Institute's Framingham Heart Study and the National Institute on Aging.
The research appears in the Feb. 28 print issue of Neurology, the medical journal of the American Academy of Neurology.