Modification in a single meal is sufficient to provoke benefits in inflammatory responses of individuals at low-to-moderate cardiometabolic risk

Abstract

Background & aims: Postprandial state is characterized by metabolic changes which may elevate circulating inflammatory biomarkers, used to assess cardiometabolic risk. It is unclear if biological benefits of certain food components could be obtained by a short-term change in a single meal of Brazilian's habitual diet. We investigated the postprandial effects of 2 fat tolerance tests (FTT) with different isocaloric meals (a typical Brazilian and a modified meal) differing by type of fatty acids and fiber contents, prior to and after breakfast interventions.

Methods: This crossover clinical trial included 80 overweight individuals with at least one cardiometabolic risk factor, (35-69 years) who received two isocaloric breakfast interventions for 4 weeks, with a 2-week washout. The Brazilian breakfast was saturated fat-enriched while the modified one was rich in unsaturated fatty acids and fibers. Before and after intervention periods, individuals underwent two FTT with meals with similar composition to the interventions breakfasts but higher energy content. Variables were compared by repeated-measures ANOVA. Correlations were assessed by Pearson's coefficient.

Results: At the end of both interventions, participants did not change plasma glucose or triglycerides. The higher IL-6 and IL-8 responses to the FTT with the Brazilian meal compared to that with the modified meal was accentuated after the interventions (p-diet <0.01; p-time <0.01). Acutely, E-selectin, TNF-α, IFN-γ, IL-10 and IL-17 concentrations did not increase in response to the FTTs, but showed higher values only after the Brazilian intervention. In contrast, intervention with the modified breakfast induced reductions in fasting and postprandial cytokines (p-diet <0.01). Changes in MUFA and PUFA intakes were inversely correlated to changes in inflammatory markers, while changes in saturated fat intake were directly correlated to IFN-γ and IL-6.

Conclusion: Isocaloric meals with distinct nutrient composition elicit different postprandial inflammatory responses after a relatively short intervention in a single meal. Each saturated fat-enriched meal consumed, as well as each unsaturated fat and fiber-enriched meal may induce pro- or anti-inflammatory responses that could impact on the cardiometabolic risk profile.

Keywords: Dietary intervention; Fat tolerance test; Inflammatory markers; Monounsaturated fatty acids; Saturated fatty acids.