Short term effect of four different macronutrient oral loads on metalbolic profile and flow mediated vasodilatation in healthy young men

ent macronutrients in terms of metabolic changes and flow-mediated vasodilatation (FMD). Methods: Seven healthy young adults were challenged with four different isoenergetic meals (GM: carbohydrates 100%; PM: proteins 95%+fat 5%; FM: fat 78%+proteins 10%+carbohydrates 12%; BM: carbohydrate 50%+proteins 13%+fat 37%) Blood samples and measurements of FMD of the brachial artery were obtained at baseline and 1h, 2h, 4h, 6h after meals. Results: Biochemical profiling in the postprandial phase showed an early increase of triglycerides with FM (T0 66±26 mg/dl; T2 116±22mg/dl, P<0.05) and a late increase with BM (T0 87±39mg/dl; T6 115±39, P<0.05). GM was associated with increased postprandial c-HDL (T0 42±13mg/dl; T4 46±14mg/dl, P<0.001) and an early and transient increase of glycaemia (T0 75±12mg/dl; T1 90±23, P=0.05). GM was associated with a 43% FMD reduction and reduction of resistance index (RI) (T0 -28%; T6 -42%). FMD after PM was increased up to the 6th hour (T0 10%; T6 14%); while RI were significantly reduced. FM decreased FMD by 59% at the 6th hour; while RI was reduced after 1 hour and showed a 18% increase in the late postprandial phase. BM decreased by 36% FMD with a 31% reduction of RI at T4. Conclusions: We observed an adverse effect of FM on postprandial triglyceridemia and a positive effect of GM on c-HDL. GM, FM and BM, but not PM, decrease FMD. GM, PM, BM decrease RI maximally after 4 hours while FM decrease RI only 1 hour after baseline