Association of Body Composition, Glucose Control, and Diet with Postprandial Triglycerides and Vascular Function

Abstract

Abstract Objectives Excessive postprandial lipemia (PPL) following intake of a high-fat meal (HFM) is a risk factor for cardiovascular disease (CVD). We recently observed significantly lesser PPL in more active individuals, irrespective of age. This project examined the association of body composition, glucose control, and dietary intake with postprandial triglycerides (TG) and vascular function in groups that differed by age and physical activity level. Methods We recruited 4 groups of adults: younger active (YA; age 22.1 ± 1.4 y; n = 9), younger inactive (YI; age 22.6 ± 3.7 y; n = 8), older active (OA; age 68.4 ± 7.7 y; n = 8), and older inactive (OI; age 67.7 ± 7.2 y; n = 7). Participants completed a 3-day food record including 2 weekdays and 1 weekend day. Following a 10-hour overnight fast and 2 days of exercise avoidance, participants consumed a HFM (12 kcal/kg; 63% fat, 34% carbohydrate). Serial blood draws were then collected every hour for 6 hours to measure metabolic responses. Vascular function was assessed using flow-mediated dilation (FMD) at baseline (BL), 2-hours, and 4-hours post-meal. Fasting insulin and glycated hemoglobin (HbA1c) were measured pre-meal. Body composition was assessed using bioelectrical impedance analysis (Seca mBCA 514). Results After controlling for physical activity and age via partial correlation, visceral adiposity was associated with TG total area under the curve (P = 0.04; r = 0.38), while body fat % was inversely associated with BL FMD (P = 0.0007; r = −0.50). HOMA-IR was not associated with visceral adiposity or body fat % (P’s ≥ 0.08). Postprandial metabolic and vascular responses were not associated with skeletal muscle mass (P’s ≥ 0.07), fasting insulin (P’s ≥ 0.30), HOMA-IR (P’s ≥ 0.40) or HbA1c (P’s ≥ 0.29). After adjusting for total caloric intake, BL FMD was positively associated with dietary fiber (P = 0.006; r = 0.50) and negatively associated with dietary sugar (P = 0.01; r = −0.46). Conclusions This study identified body fat distribution, sugar, and fiber as correlated factors for postprandial metabolic and vascular responses when also considering age and physical activity. This warrants future studies to examine further the role of these factors in determining PPL and vascular function. Funding Sources This study was funded by the College of Human Sciences at Oklahoma State University.