Autumn Lawrence, B.Sc: No relevant financial relationship(s) with ineligible companies to disclose.
Objectives: Chronic high-fat diets have been shown to disrupt glucose metabolism but the metabolic changes that occur during the acute postprandial period following a single high-fat meal are not fully understood. Our objective is to compare the postprandial availability of metabolites 5h post consumption of meals containing 25, 50, or 75% fat. We hypothesize that postprandial glycemia (primary outcome) and lipidemia (secondary outcome) will be higher with increasing quantities of fat.
Methods: Twenty healthy, recreationally active adults (50% male, 18-35 y, body mass index (BMI): 18.5-30.0 kg/m2) will be recruited for this double-blind, randomized, 3-way crossover study. Following an overnight fast participants will consume three mixed macronutrient dairy-based liquid meals containing 25, 50, and 75% energy from fat (15 kcal/kg body mass, 15% energy from protein) on separate visits with a minimum 1-week washout. Serial blood samples will be drawn throughout the entire 5h postprandial period for the measurement of glucose, insulin, triglycerides, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. Our full dataset will be analyzed using one-way repeated measures ANOVA with fat content as a factor (25 vs 50 vs 75%) and Tukey’s post hoc test to identify specific pairwise comparisons. Group data are means ± SD.
Results: To date, n=11 participants have completed the study and biochemical analysis is currently underway. At baseline, participants were 20 ± 5 y of age (n=8 males), normal weight based on BMI (23.9 ± 2.9 kg/m2), aerobically fit (VO2peak = 42.2 ± 3.3 mL/min/kg) and had healthy fasting blood glucose (5.3 ± 0.2 mM). Blinded biochemical data is available for n=1 male participant. Glucose concentrations peaked at 5.8 mM (30 min), 5.3 mM (210 min), and 7.0 mM (45 min) for visits 1, 2, and 3, respectively. This corresponds to a 9%, 0%, and 32% increase from baseline for each respective visit. Triglyceride concentrations peaked at 0.9 mM (300 min), 1.4 mM (210 min), and 0.6 mM (210 min) for visits 1, 2, and 3, respectively).
Conclusions: Our preliminary data suggest that the fat load of a single meal may alter peak postprandial glucose concentrations. Statistical analysis on the full, unblinded dataset is required to identify patterns and confirm these preliminary findings.
Funding Sources: Canadian Institutes of Health Research CGS-M
