The Cognitive Effects of Maqui Berry Extract and Fish Oil in Adults with Type 2 Diabetes

Fish oil has been extensively researched for its protective effects on cognition. More recently, anthocyanins have also gained the attention of the medical community for their potential cognitive benefits. Maqui berries are one of the richest sources of anthocyanins known to science. While there are many randomized controlled trials (RCT) investigating the effects of fish oil and/or anthocyanins on cognition in various populations, there are no RCT that exclusively investigate the cognitive effects of these compounds in adults with Type 2 Diabetes (DM2). The purpose of this double-blinded, placebo-controlled RCT was to investigate the cognitive effects of maqui berry extract and fish oil supplements in adults with DM2 over the course of eight weeks. Adults with DM2 (n=29) were recruited by the researchers and randomized to either Group A or Group B. Because the study is ongoing, it is unknown which group received the intervention. The study used the Stroop Test and Trail Making Test (TMT) to measure cognition at baseline, 4 weeks, and 8 weeks. Anthropometrics, blood glucose, and hemoglobin A1C were also taken at these time points. Sixteen female participants were included in the final analysis. Neither group showed significant improvements in the cognitive tests. However, in Group A, the effect sizes were large for the change in Trail-Making Test A (0.167), Trail Making Test B (0.261), and Trail Making Test B minus A (0.296) scores. In Group A, the change in Trail Making Test B minus A scores between baseline and week 4, and between baseline and week 8 was significant (p=0.053) and produced a large effect size (0.258). The results suggest that fish oil and maqui berry extract may improve cognition in adults with DM2, but further studies with larger sample sizes are needed.