The Effect of a Weight Reducing Diet (Containing Fish, Walnut or Their Combination) on Inflammatory Factors and Lipid Indices in Overweight and Obese Women: A Randomized Clinical Trial

There are several reports regarding the beneficial effects of omega-3 fatty acids on inflammatory factors and lipid profile. However, different sources of this kind of fatty acids have not been much studied. The objective of this study was to compare the effects of consumption of walnut (plant source of omega-3 fatty acid) salmon fish (marine source of omega-3 fatty acid) and their combination on inflammatory factors and serum levels of lipids in overweight and obese women. In this clinical trial study, 99 overweight and obese women underwent three weight reducing interventions, including diets with fish (300g per week), walnut (18walnuts per week) or combination of fish and walnut (150g fish and 9walnuts per week) for 12weeks. Inflammatory factors and serum lipids were measured at baseline and the end of the study. ANCOVA test was used to analyze the data. The decrees in LDL (p=0.03), hs-CRP (p<0.01), TNF-α (p=0.01), and IL-6 (p<0.01) and increase in HDL (p<0.01) in the combination of fish and walnut group was significantly higher compared to fish group and walnut group. A decrease was also observed in triglyceride (TG) in the fish group compared to other groups (p=0.07), although this difference was not significant. Changes in weight and waist circumference in the combination of fish and walnut group was relatively significant compared to other groups. The results of this study showed that the effect of combined use of plant and marine sources of omega-3 fatty acids on the reduction of inflammatory factors and improvement of the lipid profile, is more beneficial than the separate consumption of fish or walnut.