Effects of different dietary fat types on postprandial appetite and energy expenditure.
OBJECTIVE
Observational studies suggest that monounsaturated (MUFA) and trans fatty acids (TRANS) are more fattening than polyunsaturated fatty acids (PUFA). Therefore, the aim of this study was to investigate the acute effect of intake of PUFA, MUFA, or TRANS on appetite and energy expenditure (EE).


METHODS
Three test meals were randomly given in a cross-over design to 19 overweight (BMI: 26.8 +/- 0.4 kg/m2), young (25.2 +/- 0.7 years) men. The fat-rich breakfasts (0.8 g fat/kg body weight, 60% energy from fat) varied only in the source of C:18-fat. EE was measured continuously in a respiration chamber, and appetite sensations were rated by visual analog scales before and every 30 minutes, for 5 hours, after the meal. After 5 hours, an ad libitum meal was served, and energy intake was registered. Sensory evaluations of all meals were given using visual analog scales. Data were analyzed by two-way ANOVA.


RESULTS
There were no differences in basal or postprandial values of appetite ratings and EE, in subsequent ad libitum energy intake, or in the sensory evaluation of the test meals among the 3 test days.


CONCLUSIONS
Giving acutely large amounts of MUFA, PUFA, or TRANS did not impose any differences in appetite and EE in overweight humans. However, studies with extended protocols and other subject groups are warranted to investigate the long-term effect of dietary fat quality on the regulation of energy balance and body weight.
Flint
Anne
A
Department of Human Nutrition, Center for Advanced Food Studies, The Royal Veterinary and Agricultrual University, Frederiksberg C, Denmark. afl@kvl.dk
Helt
Berit
B
Raben
Anne
A
Toubro
Søren
S
Astrup
Arne
A
D000328:Adult; D001066:Appetite / Q000187:drug effects* / Q000502:physiology; D001481:Basal Metabolism / Q000187:drug effects / Q000502:physiology; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000378:metabolism / Q000494:pharmacology*; D004326:Drinking / Q000187:drug effects; D002149:Energy Intake / Q000187:drug effects; D004734:Energy Metabolism / Q000187:drug effects* / Q000502:physiology; D005229:Fatty Acids, Monounsaturated / Q000378:metabolism / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D008297:Male; D019518:Postprandial Period / Q000187:drug effects* / Q000502:physiology; D044242:Trans Fatty Acids / Q000378:metabolism / Q000494:pharmacology*
D004041:Dietary Fats; D005229:Fatty Acids, Monounsaturated; D005231:Fatty Acids, Unsaturated; D044242:Trans Fatty Acids