(NaturalNews) Omega-3 fatty acids may slow the brain shrinkage associated with aging and dementia, according to a study conducted by researchers from the University of South Dakota in Sioux Falls and published in the journal Neurology.
The researchers found that people who consumed the most omega-3s had brains that appeared one to two years younger than those who consumed less. Although the brain naturally shrinks with age, the rate of shrinkage is considered an important warning sign for Alzheimer’s disease and other forms of dementia.
“The brain gets smaller during the normal aging process - about 0.5 percent per year after age 70 - but dementia is associated with an accelerated and localized process of brain shrinkage,” lead researcher James Pottala said.
Researchers have suspected for some time that omega-3s play a critical role in protecting the brain from dementia. One form of omega-3s, docosahexaenoic acid (DHA), makes up 30 to 40 percent of the fatty acids found in the brain’s cell membranes. DHA concentrations are especially high in the synapses that neurons use to communicate.
“Omega-3s are building blocks for brain cell membranes,” Pottala said.
Larger brain volume
Omega-3s come in three separate forms: DHA, eicosapentaenoic acid (EPA) and alpha-linolenic acid (ALA). DHA and EPA are found only in marine foods, including fatty fish and certain varieties of algae. ALA is found in terrestrial plants, such as flax seeds and walnuts.
The current study focused on the marine omega-3s, DHA and EPA. Researchers measured the levels of both fatty acids in the blood of 1,111 women who were taking part in the Women’s Health Initiative Memory Study. Omega-3 blood levels are considered good markers of dietary intake.
When the study began, the average participant age was 70 years, and none of the participants had ever shown any signs of dementia. The researchers conducted MRI brain scans of each participant at the study’s beginning and again eight years later.
They found that, at the end of the study, women with the highest intake of omega-3s had the largest brain volumes, even after adjusting for potential confounding factors including age, education, exercise, smoking or other health conditions. The highest level of omega-3 intake was associated with a 0.7 percent greater brain volume and a 2.7 percent greater volume of the hippocampus.
The hippocampus is a region of the brain associated with memory and is often the first area to suffer damage in Alzheimer’s disease. Of 13 brain regions examined, the hippocampus was the only one to show greater volume associated with higher omega-3 intake.
Act now to protect your brain
Pottala noted that the omega-3 levels seen in the study are very easily achievable.
“These higher levels of fatty acids can be achieved through diet and the use of supplements, and the results suggest that the effect on brain volume is the equivalent of delaying the normal loss of brain cells that comes with aging by one to two years,” Pottala said.
Ronald Petersen, director of the Mayo Clinic Alzheimer’s Disease Research Center, welcomed the findings, noting that they “suggest there is a positive relationship between omega-3 fatty acid-rich diets and the preservation of brain volume in aging.”
“The take-home message is to eat a heart-healthy diet that includes fish,” he said. “I’d also recommend physical exercise and engagement in intellectual activity.”
Heather Snyder, director of medical and scientific relations for the Alzheimer’s Association, agreed that lifestyle makes a huge difference in reducing Alzheimer’s risk.
“The strongest evidence we see in the research is the benefit of physical activity for potentially reducing the risk of Alzheimer’s disease,” she said.
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