Effects of dietary fatty acid composition from a high fat meal on satiety

The composition of fats within a high-fat (HF) meal may differentially affect hunger and satiety. Purpose: Compare HF meals rich in either monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), or saturated fatty acids (SFAs) on the satiety hormone, peptide YY (PYY), and subjective feelings of hunger and fullness. Methods: Fifteen normal weight women (18–45 year) were randomized in a crossover design to complete three study visits. The three treatments (three visits) were HF meals (70% of energy from fat) rich in MUFAs (42% of total energy), PUFAs (42% of total energy), or SFAs (45% of total energy). At each visit, subjects consumed a HF meal and eight blood draws were collected over a 5 h period. A visual analog scale (VAS) was completed at the same time as each blood draw for subjective feelings of hunger and fullness. Results: The postprandial PYY response (area under the curve) was significantly lower (p < 0.05) for the MUFA-rich meal (MUFA: 534.5 ± 27.2 pg/mL/5 h) vs. the SFA-rich or PUFA-rich meals (SFA: 607.3 ± 51.6 pg/mL/5 h, PUFA: 633.1 ± 35.8 pg/mL/5 h). The SFA-rich meal elicited greater subjective feelings of fullness compared to MUFA- and PUFA-rich meals (288.1 ± 9.6 vs. 236.8 ± 7.9 and 220.9 ± 7.4 mm/5 h; p = 0.04, for 5 h AUC for SFA, MUFA, and PUFA, respectively). The only significant correlations between PYY levels and VAS measures were found with the SFA-rich meal. Conclusion: Our data shows that liquid meals rich in MUFAs may elicit a weaker satiety response based on PYY levels compared to liquid meals rich in PUFAs or SFAs in normal weight women.