Sequential meals containing animal and plant based saturated fats have differential effects on postprandial gut hormones but no impact on satiety compared with unsaturated fats in generally healthy men: findings from the randomized controlled crossov

Background: Saturated fat (SFA)-rich meals are often linked to elevated postprandial triacylglycerol responses compared with unsaturated fats. Despite the growing popularity of coconut oil in the UK diet, effects of this SFA-rich oil on postprandial lipemia and physiological appetite responses are unclear. Objective: This study compared sequential high-fat test meals rich in butter and coconut oil with a vegetable oil blend (safflower and olive oil) on postprandial triacylglycerol (primary outcome), lipids, glucose and gut hormones responses, and physiological measures of appetite in healthy men. Methods: In a single-blind, randomized acute three-armed crossover study, 13 men (53±3 years, BMI 24.4±3.0 kg/m2) consumed sequential test meals containing SFA-rich oils/fats or a vegetable oil blend (breakfast 53.6 g and lunch 33.6 g fat) on three occasions, each separated by a four-week period. Blood samples and satiety ratings were collected prior to and at regular intervals over 480 min post-test breakfast. Blood pressure and arterial stiffness were measured at 0, 150, 300 and 480 min. Postprandial data were analyzed using linear mixed models and satiety ratings using ANCOVA. Results: Postprandial triacylglycerol, glucose, insulin, ghrelin, blood pressure and arterial stiffness or perceived satiety responses were similar between the test fat/oils. The incremental area under the curve (iAUC) for the postprandial glucose-dependent insulinotropic polypeptide response was higher with vegetable oil versus the SFA-rich meals whereas the glucagon-like peptide-1 response was lower after the butter than coconut and vegetable oil-rich meals (p≤ 0.012). The iAUC for the peptide YY response was lower after butter than coconut oil-rich meals (p≤ 0.048), but not different versus vegetable oil. Conclusion: Despite varying fatty acid compositions, postprandial triacylglycerol responses were similar between fats/oils. Our findings suggest that butter and coconut oil have differential effects on gut hormone responses compared with unsaturated fats without an impact on satiety in generally healthy men.