Influence of medium-chain and long-chain triacylglycerols on the control of food intake in men

Abstract

Hunger may be delayed and food intake reduced under metabolic conditions that spare carbohydrate oxidation, especially during oxidation of medium-chain triacylglycerols (MCTs) or monounsaturated triacylglycerols. In 12 healthy, adult, male volunteers isolated and deprived of any time cues, we compared the effects of 4 high-carbohydrate breakfasts (1670 kJ) supplemented either with a fat substitute (Sub; 70 kJ) or with 1460 kJ fat as monounsaturated long-chain triacylglycerols (LCT-U), saturated long-chain triacylglycerols (LCT-S), or MCTs. In the first session we investigated the effects of these breakfasts on the following food intake variables: hunger ratings at repeated intervals, the time until the spontaneous request for the next 2 free-choice meals, and the amount of food consumed. In a second session with fixed lunches, we studied the effects of the same breakfasts on plasma glucose, insulin, triacylglycerol, fatty acid, and beta-hydroxybutyrate concentrations. The addition of any of the fats to the high-carbohydrate breakfasts did not alter hunger ratings, but significantly delayed the request for lunch compared with the low-fat breakfast. The free-choice lunch eaten after the MCT breakfast was also significantly smaller. Blood glucose and insulin concentrations were lower after the 3 fat breakfasts, followed by larger increases in glucose and enhanced insulin responses 30 min after the lunch. No differences were observed between the LCT-U and LCT-S conditions. We conclude that MCTs decreased food intake by a postabsorptive mechanism, although the exact effect of these lipids on carbohydrate oxidation will require further studies involving nutrient balance measurements.

Dose–response effects of a novel fat emulsion (Olibra™) on energy and macronutrient intakes up to 36 h post-consumption

“…Furthermore, different physicochemical properties of fats could influence their satiating properties. These include fatty acid chain length (Bach et al, 1996;Stubbs & Harbon, 1996;Van Wymelbeke et al, 1998), degree of fatty acid unsaturation (Shimomura et al, 1990;Lawton et al, 1997;Kamphuis et al, 2001), degree of emulsification (Welch et al, 1985(Welch et al, , 1988 and emulsion stability (Armand et al, 1992). In this context it has recently been shown that a fat emulsion (Olibra TM ) formulated from palm oil and oat oil fractions significantly decreased energy and macronutrient intakes in lean, overweight and obese subjects up to 36 h post-consumption (Burns et al, 2000(Burns et al, , 2001.…”

Short-term effects of yoghurt containing a novel fat emulsion on energy and macronutrient intakes in non-obese subjects

“…For example, medium-chain triacylglycerols appear to increase satiety and decrease energy intake to a greater extent than long chain triacylglycerols. 5,6 Furthermore, in normal weight men and in obese men, 7 fats infused into the small intestine in the form of triacylglycerol emulsion have been shown to suppress short-term hunger ratings and food intake to a greater extent than an isoenergetic infusion of carbohydrate.…”

Effect of Macronutrient Composition on Short-Term Food Intake and Weight Loss

“…Thus, MCTs may contribute to spontaneous energy-intake reduction and greater weight loss than LCTs (13). For example, the addition of 38 g of fat as monounsaturated LCTs, saturated LCTs, or MCTs to high-carbohydrate breakfasts delayed the request for subsequent FI compared with the low-fat breakfast in healthy adults (14). Furthermore, both high-LCT breakfasts led to the highest energy intake at lunch and dinner, but it was the MCT breakfast that resulted in the lowest FI, suggesting that, despite the high energy density of high-fat meals, the high-MCT diet enhances satiation and the suppression of FI.…”