A randomized, double-blind, crossover design study was conducted to test the acute effects of high fat meals enriched with (1) saturated fatty acids (SFA); (2) monounsaturated fatty acids (MUFA); (3) polyunsaturated fatty acids (PUFA) vs. (4) a low fat/high carbohydrate (CARB) meal on postprandial insulinaemic, lipaemic and inflammatory responses, as well as gastrointestinal peptide secretion and satiation on 30 metabolic syndrome subjects (15 men and 15 women). Primary outcome of this study is postprandial changes of C-peptide. Other measured outcomes including insulin and glucose responses, lipids, cytokines and gastrointestinal peptides. Subjective appetite measurements were taken as exploratory outcomes using visual analogue scales.