OVERFEEDING FAT AS MONOGLYCERIDE OR TRIGLYCERIDE - EFFECT ON APPETITE, NUTRIENT BALANCE AND THE SUBSEQUENT DAYS ENERGY-INTAKE

Objective: To examine the effect of overfeeding isoenergetic diets enr iched in 1-monoglyceride or triglyceride on nutrient oxidation and app etite throughout the day that it was given and the subsequent day's fo od 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 twi ce in a 3 d protocol. On day 1 (maintenance day) they were fed a mediu m fat (MF) maintenance diet CMF: 40% fat, 47% carbohydrate and 13% pro tein by energy) calculated at 1.6 x resting metabolic rate (RMR). Subj ects entered the calorimeter at 06.30 on day 2 for 49.5 h. On day 2 (m anipulation day) subjects consumed a MF diet at 1.6 x RMR with an addi tional 0.45 x RMR as either I-monoglyceride or triglyceride. On day 3 (outcome day), subjects had ad libitum access to isoenergetic, isoener getically dense MF (40:47:13,550 kJ/100 g) foods. Subjective hunger an d satiety were tracked hourly, during waking hours throughout days 1-3 , Results: There was no significant effect of diet on nutrient oxidati on or balance either during day 2 (manipulation day) or day 3 (outcome day), fat oxidation was similar on both diets. Subjective hunger was nor affected by diet on either day with mean values of 34.3 and 35.0 m m (SED 5.2 on manipulation day (day 2) and outcome day (day 3), 35.3 a nd 40.8 mm (SED 5.2) on the I-monoglyceride or triglyceride diets resp ectively. 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 ma nner that is very similar to triglyceride, in its effects on appetite, feeding behaviour and net nutrient balance.