Impact of exercise and dietary fatty acid composition from a high-fat diet on markers of hunger and satiety

To compare the effects of both dietary fatty acid composition and exercise vs. sedentary conditions on circulating levels of hunger and satiety hormones. Eight healthy males were randomized in a 2 × 2 crossover design. The four treatments were 3 days of HF diets (50% of energy) containing high saturated fat (22% of energy) with exercise (SE) or sedentary (SS) conditions, and high monounsaturated fat (30% of energy) with exercise (UE) or sedentary (US) conditions. Cycling exercise was completed at 45% of VO2max for 2 h daily. On the third HF day, 20 blood samples were drawn over a 24 h period for each hormone (leptin, insulin, ghrelin, and peptide YY (PYY)). A visual analog scale (VAS) was completed hourly between 0800 and 2200. Average 24 h leptin and insulin levels were lower while 24 h PYY was higher during exercise vs. sedentary conditions. FA composition did not differentially affect 24 h hormone values. VAS scores for hunger and fullness did not differ between any treatment but did correlate with ghrelin, leptin, and insulin. High saturated or unsaturated fat diets did not differ with respect to markers of hunger or satiety. Exercise decreased 24 h leptin and insulin while increasing PYY regardless of FA composition.