Background: Omega 3 fatty acids, such as docosahexaenoic acid (DHA) have been widely consumed as supplements to control chronic inflammation. Nanocapsules containing DHA (MLNC-DHA-a1) were developed and showed excellent stability. Thus, our objective was to evaluate the effect of MLNC-DHA-a1 nanocapsules on biomarkers of chronic inflammation. Methods: Cells viability was determined by flow cytometry. The uptake of MLNC-DHA-a1 nanocapsules by macrophages and their polarization were determined. In vivo, LDLr (-,-) mice were fed a Western diet to promote chronic inflammation and were treated with MLNC-DHA-a1 nanocapsules, intravenously injected via the caudal vein once a week for 8 weeks. Results: MLNC-DHA-a1 nanocapsules decreased the concentration of TNFα (p = 0.02) in RAW 264.7 cells compared to the non-treated group (NT), with no changes in IL-10 (p = 0.29). The nanocapsules also exhibited an increase in the M2 (F4/80+ CD206) phenotype (p