Comparison of two feeding regimens on peripheral vascular function and biomarker variability

Diets high in fat are associated with endothelial dysfunction and cardiovascular events. Frequent meals extend the postprandial state. To establish a model to study these phenomena, 10 males (age 19–30 y, BMI 18.5–24.9 kg/m 2 , body surface area‐BSA 1.5–2.2 m 2 ) were assigned to 2 feeding regimens (standard and BSA‐based), in random order, on different days separated by 1‐week (single‐blind, 2×4 crossover design). Each regimen contained breakfast (0 h) and lunch (4 h). Each meal in regimen 1 provided 850 kcal; each meal in regimen 2 provided 460 kcal/m 2 BSA. Five markers were measured at times 0, 2, 4, 6 h: reactive hyperemia index (RHI), heart rate (HR), blood glucose and triglyceride and plasma malondialdehyde (TBARS). RHI increased from fasting to postprandial state (P=0.01) but the increment post lunch was smaller than post breakfast (P=0.03). TBARS increased at 2 h and decreased at 4 h after breakfast (P<0.05), and remained unchanged after lunch (P>0.05). Postprandial HR (2, 6 h) was higher than pre‐meal HR (0, 4 h; P<0.05). Regimen 2 (η p 2 RHI =0.32, ω 2 RHI =0.07; η p 2 HR =0.39, ω 2 HR =0.27) may be a more effective model than regimen 1 (η p 2 RHI =0.12, ω 2 RHI =0; η p 2 HR =0.29, ω 2 HR =0.16) due to greater effect sizes. More subjects are needed to confirm this finding since power was too low (1‐β<0.6) to detect a regimen×time effect (P RHI =0.42, P TBARS =0.65) or to differentiate between regimens (P RHI =0.46, P TBARS =0.17). Research funding: Indiana University.Grant Funding Source : Indiana University