Overfeeding fat as monoglyceride or triglyceride: effect on appetite, nutrient balance and the subsequent day's energy intake

Abstract

Objective: To examine the effect of overfeeding isoenergetic diets enriched in 1-monoglyceride or triglyceride on nutrient oxidation and appetite throughout the day that it was given and the subsequent day's food and energy intake. Design: Six men [mean (s.d.) weight; 76.89 (7.00) kg, height; 1.77 (0.05) m, age; 26.4 (6.0) y], were each studied twice in a 3 d protocol. On day 1 (maintenance day) they were fed a medium fat (MF) maintenance diet (MF: 40% fat, 47% carbohydrate and 13% protein by energy) calculated at 1.66resting metabolic rate (RMR). Subjects entered the calorimeter at 06.30 on day 2 for 49.5 h. On day 2 (manipulation day) subjects consumed a MF diet at 1.66RMR with an additional 0.456RMR as either 1-monoglyceride or triglyceride. On day 3 (outcome day), subjects had ad libitum access to isoenergetic, isoenergetically dense MF (40 : 47 : 13, 550 kJ/ 100 g) foods. Subjective hunger and satiety were tracked hourly, during waking hours throughout days 1±3. Results: There was no signi®cant effect of diet on nutrient oxidation or balance either during day 2 (manipulation day) or day 3 (outcome day), fat oxidation was similar on both diets. Subjective hunger was not affected by diet on either day with mean values of 34.3 and 35.0 mm (SED 5.2) on manipulation day (day 2) and outcome day (day 3), 35.3 and 40.8 mm (SED 5.2) on the 1-monoglyceride or triglyceride diets respectively. Day 3 food and energy intake were unaffected by the previous day's dietary treatment, with mean intakes of 15.9 and 15.6 MJ (SED 1.07) on the 1-monoglyceride or triglyceride treatments, respectively. Conclusions: This study suggests that when 1-monoglyceride is covertly incorporated into a diet at unusually high levels, it behaves in a manner that is very similar to triglyceride, in its effects on appetite, feeding behaviour and net nutrient balance. Sponsorship: This work was supported by the Scottish Of®ce Agriculture, Environment and Fisheries Department. Descriptors: monoglyceride; triglyceride; fat; energy; macronutrients; food intake; appetite; humans; calorimetry IntroductionThe role of high-fat, energy-dense diets in bringing about excess energy intakes (Lissner et al, 1987;Thomas et al, 1992) and their contribution to the current secular trends in overweight and obesity is now well documented (Department of Health, 1992).Increased intake of dietary fat is believed to facilitate overconsumption because it increases the palatability and energy density of the diet (Blundell et al, 1995), both of which appear to facilitate higher energy intakes. Once ingested, dietary fat appears to exert poor postabsorptive feedback onto subsequent intake (Stubbs, 1995). It has been suggested that nutrient oxidation is an important component of satiety, and since dietary fat is preferentially stored, rather than oxidised, it may well contribute less to postabsorptive satiety than the macronutrients protein and carbohydrate. The intake of these macronutrients stimulate autoregulatory increases in their own oxidation (Abbot et al, 1988). It h...

Diet composition and energy intake in humans

“…Fat produced less than caloric compensation [ 83 ]. Similar findings have been observed in short-term laboratory studies on appetite control, where protein has shown greater satiating effects compared with CHO [ 86 – 90 ], particularly when given at moderate and large amounts greater than approximately 1.5 MJ [ 91 ]. However, small manipulations below approximately 1.2 MJ often do not reveal differences in the satiating efficiency of macronutrients.…”

“…Some studies suggest that fat influences appetite and EI, albeit to a modest extent, regardless of its contribution to ED. CHO exerts a more immediate impact on satiety than fat [ 91 ]. A few studies have found this relatively subtle effect to be independent of ED, e.g.…”

“…For instance, when individuals were provided with isoenergetically dense diets containing an excess of 4 MJ d −1 of protein, CHOs or fat, protein had a significant and substantial impact on reducing the motivation to eat compared with CHO and fat-enriched foods. The disparities between CHOs and fat could be attributed to CHOs exerting a more immediate satiety effect than fat [ 91 ].…”

Effects of Different Dietary Fat Types on Postprandial Appetite and Energy Expenditure

“…Although we used a large amount of MUFA, PUFA, or TRANS in the test meals (∼57% energy), we saw no differences in either postprandial appetite registrations, subsequent ad libitum EI, or EE. This lack of effect does not seem to be a result of a lack of sensitivity of the subjective appetite ratings because they have been shown in a number of studies to be sensitive to nutritional and other manipulations (21, 33, 34, 35). Also, differences in ratings caused by time‐course effects were detectable in this study, with satiety falling and rising according to meal times, and the appetite ratings were not influenced by different sensory evaluations of the test meals.…”