Omega-3s Protect Brain Health and Size
Brain: Omega-3 Support Brain Health and Size
High levels of Omega-3 appear to slow down brain volume loss during aging. Postmenopausal women with elevated concentrations of the fatty acids DPA (docosapentaenoic acid) and EPA (eicosapentaenoic acid) have, compared to others of the same age, larger brains. This condition equates to preserving brain health for one or two years.
This is the result of a study conducted by researchers at the University of South Dakota (USA), published in the journal Neurology, which investigated the effect of Omega-3s on brain volume reduction, a phenomenon occurring during normal aging and in Alzheimer’s patients.
Omega-3 and their effect on the brain
EPA and DHA are fundamental components of cell membranes, providing the fluidity necessary for processes such as movement, division, growth, and communication. In neuron membranes, the most represented Omega-3 is DHA; an adult brain contains about 20 grams of it. It is essential for the growth and maintenance of nervous tissue integrity and consequently for neuronal excitability and synaptic function. In red blood cells, the total EPA and DHA in the membrane, expressed as a percentage of total fatty acids, is called the Omega-3 Index. It is a useful indicator of the amount of EPA and DHA in the blood.
The Omega-3 Index influences brain size
The study involved 1,111 postmenopausal women, whose EPA and DHA concentrations in red blood cells were analyzed. After 8 years, when the average age was 78, brain volume was measured by MRI. This analysis showed that subjects with higher EPA and DHA concentrations also had larger brain volumes.
For example, women with an Omega-3 Index of 7.5% showed a brain volume 0.7% larger compared to those with an index of 3.4%. Moreover, those with higher DHA and EPA amounts also had a 2.7% larger hippocampus volume, the brain area responsible for memory and the first to atrophy and shrink in Alzheimer’s disease.
EPA and DHA deficiency may promote hippocampal atrophy
Researchers suggest that the correlation between a high Omega-3 Index and greater brain and hippocampus volume is due to the protective action EPA and DHA exert on nerve cells. Omega-3s, by limiting brain volume loss, would slow neuronal aging by one or two years. As the authors suggest, protective Omega-3 levels for the brain can be reached through diet and specific supplements.
Scientists hypothesize that a low Omega-3 Index may increase the risk of hippocampal atrophy, while normal aging causes generalized brain atrophy. Further studies are planned to determine whether maintaining high EPA and DHA percentages can slow atrophy rates in just the hippocampus or the entire brain.
Source: James V. Pottala, Kristine Yaffe, Jennifer G. Robinson, MPH, Mark A. Espeland, Robert Wallace, and William S. Harris, “Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes” Neurology, 2014 Jan 22
