As described in detail in a recent article by Dinah (see link here for further reading http://brainbased.info/the-effects-of-air-pollution-on-brain-development), air pollution (specifically fine pollutant PM2.5 particles) has many dangerous effects on our body, and toxic effects on our nervous system and brain development. As mentioned in the article, many epidemiological studies have implicated PM2.5 exposure as especially harmful to children, as their brain continues to develop across childhood and their 30s. The study included in the article gave results showing that annual residential PM2.5 exposure was associated with hemispheric and region-specific differences in grey matter. And although no associations were found with cognitive function, the study demonstrated that at relatively low levels current PM2.5 exposure may be an important environmental factor that influences patterns of neurological development in children.
With all this being said, we can see the importance of being able to shield oneself from the possible harmful effects of fine pollutant PM2.5 particles and other substances found in air pollution. And in luck we are! According to researchers who analysed data from a prospective cohort study, omega-3s can play a key part in protecting your brain from the dangerous and toxic effects of air pollution.
The researchers of this study were interested in the neurotoxic effects of PM2.5 exposure on normal-appearing brain volumes among dementia-free healthy elderly women, and looked to correlate that with those participants’ omega-3 indexes (LCn3PUFA is an example of an omega-3 fatty acid, and this was used for analysis in the study). The data used came from a larger observational cohort study carried out in 1996-1999 called the Women’s Health Initiative Clinical Trials (WHI-CT); this was a clinical trial of a postmenopausal hormone therapy which included over 7,000 participants. In 2005 almost 1,400 of these women underwent MRIs and were grouped into a subsidiary study called Women’s Health Initiative Memory Study-Magnetic Resonance Imaging (WHIMS-MRI). It was the stored blood of these women that was analysed for the present research in question. Out of the women from the MRI study, 88 were not included in the current research because their blood did not give valid omega-3 measurements, and so the researchers were left with 1,315 participants with an average age of 70.
Based on prospectively collected and geocoded participant addresses, the researchers were able to produce a spatiotemporal model (accounts for space/location and time) to estimate the 3-year average PM2.5 exposure before the MRI. They then correlated the baseline LCn3PUFAs in the women’s red blood cells with the estimates of their PM2.5 exposure with their brain volumes in generalised linear models. Following adjustments for possible cofounders, the researchers found that participants with higher levels of LCn3PUFA in their red blood cells had significantly greater volumes of white matter and hippocampus. The women in the highest quartile of omega-3 index values were protected best against the brain damaging effects of PM2.5 exposure, as shown by the study’s results of larger volumes of white matter measured by the MRIs.
Omega-3s from foods such as fish may help preserve the brain’s volume of white matter, which is responsible for sending signals throughout your brain, and the size of the hippocampus, which is vital for memory formation, as women age. And so, findings from this prospective cohort study among elderly women suggest that the benefits of LC3nPUFAs on brain ageing may include the protection against potential adverse effects of air pollution on white matter volumes.
Original source: C Chen, P Xun, J.D. Kaufman, K.M. Hayden, M.A. Espeland, E.A. Whitsel, M.L. Serre, W Vizuete, T Orchard, W.S. Harris, X Wang, H.C. Chui, J Chen and K He. (August 2020).”Erythrocyte omega-3 index, ambient fine particle exposure and brain aging”. Neurology. 95;(8).