Modification of a Brazilian meal including Mediterranean components induces cardiometabolic benefits

INTRODUCTION: Changes in dietary pattern and physical activity of populations have elevated the incidence of chronic non-communicable diseases associated with increased adiposity. Evidence has shown that populations consuming Mediterranean diets have lower mortality from all causes, including cardiovascular diseases. The benefits of this diet rich in fiber and unsaturated fats, derived in part on the effects of these nutrients on inflammatory condition that triggers cardiometabolic diseases. OBJECTIVE: This study investigated the effects of changing a meal of Brazilian menu, the breakfast, in order to approximate it to the Mediterranean pattern on lipid and glucose metabolism, subclinical inflammation and also on the expression of inflammatory genes. METHODS: This study was a crossover trial lasting a total of 10 weeks, including 80 overweight adults, nondiabetic without drug treatment for dyslipidemia. Participants who met the inclusion criteria underwent two 4-week interventions in breakfast, with wash-out of two weeks between them. The breakfasts (Brazilian and modified) were isocaloric, differing according to fiber and types of fatty acids contents. Before and after each intervention, fat tolerance tests with meals rich in fat (saturated and unsaturated depending on the intervention) were perfomed, with blood sample collections for glucose, insulin, lipids and inflammatory markers up to 240 minutes. Also, expression of inflammatory genes before and after each intervention was analyzed. To compare the acute and sub-acute responses to interventions were used Student t test or the corresponding nonparametric test and ANOVA for repeated measures. For expression of the genes, delta CT method was used and the relative expression calculated based on fasting and pre-intervention values. P value <0.05 was considered significant. RESULTS: In Article 1 (Modification in a single meal is sufficient to provoke benefits in inflammatory responses of Individuals at low-to-moderate cardiometabolic risk), we observed higher IL-6 and IL-8 concentrations after ingestion of the Brazilian FTT compared with the modified one, whose elevations were even more pronounced after the intervention period. Higher concentrations of E-selectin, TNF-α, IFN-γ, IL-10 and IL-17 were found at fasting and in postprandial state only after the Brazilian intervention. In Article 2 (Inflammatory and metabolic response to dietary intervention Differs Among Individuals at distinct cardiometabolic risk levels), the intervention with the modified breakfast decreased waist circumference and blood pressure and increased the concentrations HDL (p <0.05). Participants with metabolic syndrome showed improvements in traditional risk factors (blood pressure and plasma glucose and apolipoprotein B) whit the modified breakfast, while those without the syndrome improved inflammatory markers. Article 3 (Comparison of inflammatory gene expression and their circulating products after short-term interventions fatty acids in humans) showed that the Brazilian FTT induced higher expression of IL-1β compared to the modified one, before and after the interventions. A tendency for higher postprandial expression of IFN-γ and increased IL-6 expression after intervention with Brazilian breakfast were also detected. In the meta-analysis of Article 4 (Impact of the content of fatty acids in oral fat tolerance tests on postprandial triglyceridemia: systematic review and meta-analysis) a total of 18 studies were included. When comparing the triglycerides responses to saturated and unsaturated fatty acids, lower areas under the curve with the meals rich in MUFA were observed. Postprandial triglyceridemia after PUFA was lower, but not significantly different from meals rich in saturated fat. CONCLUSIONS: Small changes in diet are able to induce benefits in cardiometabolic risk profile in a relatively short period. Such benefits are seen in routine clinical parameters, which are compatible with the favorable effects on the expression of inflammatory genes and circulating biomarkers. There is a potential acceptance of introducing components of the Mediterranean diet in non-Mediterranean populations like Brazil, which could improve the cardiometabolic risk profile in the long term.