If you're a meat-and-potatoes person, and shun eating fish, you could be harming your mental health. That's because diets short on omega-3 fatty acids, nutrients mainly found in fish, may cause your brain to age faster and lose some of its memory and thinking abilities, according to a study published February 28, 2012 in Neurology.
"People with lower blood levels of omega-3 fatty acids had lower brain volumes that were equivalent to about two years of structural brain aging," said study author Zaldy S. Tan, MD, of the Easton Center for Alzheimer's Disease Research at UCLA, in a released statement.
In an attempt to find out how omega-3 levels affect the brain, researchers gave 1,575 dementia-free people, averaging 67 years old, MRI brain scans, and tested their mental function, body mass and their red blood cells for omega-3 fatty acid levels.
Omega-3 fatty acids include the nutrients docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Folks with DHA levels in the bottom 25 percent of participants had lower brain volume compared to those with higher DHA levels. And participants with levels of all omega-3s in the bottom 25th percentile also scored lower on tests of visual memory and executive function, such as problem solving, multi-tasking and abstract thinking.
These results build upon findings from a 2004 UCLA study on mice, which showed omega-3 DHA rich diets may help those with Alzheimer's disease, protecting the brain against associated memory loss and cell damage. Researchers concluded omega-3s may help lower one's risk of Alzheimer's and help slow progression of the disorder in its later stages.
Getting your omega-3 fill
It's not enough to just eat fish once a week. Our brain absorbs DHA rapidly, so we need a constant supply for proper cognitive function, eye development and mental tasks.
For fish aficionados, choose these coldwater varieties: wild Alaskan salmon, halibut, mackerel, sardines, and herring. But eat them in moderation. The oiliness of these fish cause them to absorb more mercury, dioxin, PCP, and other harmful metals.
For non-fish lovers, there are easy ways to get omega-3s in your daily diet. Many egg producers now offer omega-3 packed eggs (the chickens have been fed a diet rich in DHAs). Manufacturers are also adding omega-3s to products such as milk, cheese, breads and pastas.
And there's always the omega-3 supplement option. Look to our buyer's guide to determine the best omega-3 fatty acid supplement for you.