Obesity is associated with chronic low-grade inflammation that can increase risk for atherosclerosis, type 2 diabetes, cancer, and poor outcomes with COVID-19. The omega-3 polyunsaturated fatty acids known as EPA and DHA, plentiful in fatty fish, have been associated with lower chronic inflammation. A small randomized study led by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University compared the effects of supplements of these two omega-3s in a small group of older adults with obesity and chronic low-grade inflammation. Lower levels of inflammatory proteins (cytokines) were found in participants’ blood after taking DHA than EPA, but EPA improved the balance between pro- and anti-inflammatory proteins. These two effects were different and complementary—each important pathways in the progression of chronic diseases.
While this study does not provide any actionable advice, it is a step toward understanding how components of our diet impact our health. Meanwhile, consuming fatty fish is an excellent way to get both of these important polyunsaturated fats (although not at the levels used in this research). Salmon, mackerel, tuna, herring, and sardines are the top sources, but eating any seafood you like twice a week is good for your health.