Older women who eat one to two servings of fish or shellfish per week may be consuming enough omega 3 foods. This means they could counteract the effects of air pollution on the brain. This emerges from a new study. The researchers found that among older women who lived in areas with high air pollution, those who had the lowestOmega-3 fatty acids in the bloodhad greater brain shrinkage than women with the highest concentrations.
Brain protection through Omega 3 foods
Fish is an excellent source of omega-3 fatty acids and can be easily incorporated into the diet. Previous study results also show that omega-3 fatty acids fight inflammation and maintain brain structure in aging brains. For this reason, researchers have found that they reduce brain damage caused by neurotoxins such as lead and mercury. The study authors therefore investigated whether fatty acids contained in omega 3 foods could have a protective effect against fine dust particles from air pollution. 1,315 women with an average age of 70 years took part in the study. At the start of the study, the subjects did not have dementia. The women also completed questionnaires about diet, physical activity and medical history.
Researchers used the dietary questionnaire to calculate the average amount of fish each woman consumed per week, including grilled or baked fish, canned fish, tuna salad and non-fried shellfish. Fried fish was not included because research has shown that deep-frying damages omega-3 fatty acids. Participants received blood tests. The researchers measured the amount of omega-3 fatty acids in their red blood cells and divided the women into four groups based on the amount of omega-3 fatty acids in their blood. The team used the women's home addresses to determine their average three-year exposure to air pollution. Participants then underwent magnetic resonance imaging (MRI) brain scans. This made it possible to measure the volume of the white matter, which consists of nerve fibers. These fibers send signals throughout the brain. Also included is the hippocampus, the part of the brain that is connected to memory.
Research results
After adjusting for age, education, smoking and other factors that could influence brain shrinkage, the researchers found that women with the highest levels of omega-3 fatty acids in their blood had more white matter. Those had 410 cubic centimeters of white matter, compared to 403 cubic centimeters for the low fatty acid group. The researchers found that for every quarter increase in air pollution, the average white matter volume decreased by 11.52 cm3 in people with lower levels of omega-3 fatty acids and by 0.12 cm3 in those with higher levels was. Women with the highest levels of omega-3 fatty acids in their blood also had larger amounts of hippocampus.
Because separate studies have found that some types of fish may contain environmental toxins, it's important to talk to a doctor about the types of fish before adding more fish to your diet. One limitation of the study was that most participants were older white women. The results cannot therefore be transferred to other people. In addition, the researchers were able toof the studyexamine only late-life exposure to air pollution, not early or midlife exposure. Future studies should therefore address exposure to air pollution across a person's lifespan.
