The metabolic interplay between dietary carbohydrate and exercise and its role in acute appetite regulation in males: a randomized controlled study

Gut hormones and appetite regulation

PURPOSE OF REVIEW

Various gut hormones interact with the brain through delicate communication, thereby influencing appetite and subsequent changes in body weight. This review summarizes the effects of gut hormones on appetite, with a focus on recent research.

RECENT FINDINGS

Ghrelin is known as an orexigenic hormone, whereas glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), cholecystokinin (CCK), postprandial peptide YY (PYY), and oxyntomodulin (OXM) are known as anorexigenic hormones. Recent human studies have revealed that gut hormones act differently in various systems, including adipose tissue, beyond appetite and energy intake, and even involve in high-order thinking. Environmental factors including meal schedule, food contents and quality, type of exercise, and sleep deprivation also play a role in the influence of gut hormone on appetite, weight change, and obesity. Recently published studies have shown that retatrutide, a triple-agonist of GLP-1, GIP, and glucagon receptor, and orforglipron, a GLP-1 receptor partial agonist, are effective in weight loss and improving various metabolic parameters associated with obesity.

SUMMARY

Various gut hormones influence appetite, and several drugs targeting these receptors have been reported to exert positive effects on weight loss in humans. Given that diverse dietary and environmental factors affect the actions of gut hormones and appetite, there is a need for integrated and largescale long-term studies in this field.

Oligofructose-Enriched Inulin Consumption Acutely Modifies Markers of Postexercise Appetite

Enhancing the effectiveness of exercise for long-term body weight management and overall health benefits may be aided through complementary dietary strategies that help to control acute postexercise energy compensation. Inulin-type fructans (ITFs) have been shown to induce satiety through the modified secretion of appetite-regulating hormones. This study investigated the acute impact of oligofructose-enriched inulin (OI) consumption after exercise on objective and subjective measures of satiety and compensatory energy intake (EI). In a randomized crossover study, following the completion of a 45 min (65-70% VO2peak) evening exercise session, participants (BMI: 26.9 ± 3.5 kg/m2, Age: 26.8 ± 6.7 yrs) received one of two beverages: (1) sweetened milk (SM) or (2) sweetened milk + 20 g OI (SM+OI). Perceived measures of hunger were reduced in SM+OI relative to SM (p = 0.009). Within SM+OI, but not SM, plasma concentrations of GLP-1 and PYY were increased and acyl-ghrelin reduced from pre-exercise to postexercise. EI during the ad libitum breakfast in the morning postexercise tended to be lower in SM+OI (p = 0.087, d = 0.31). Gastrointestinal impacts of OI were apparent with increased ratings of flatulence (p = 0.026, d = 0.57) in participants the morning after the exercise session. Overall, the ingestion of a single dose of OI after an exercise session appears to induce subtle reductions in appetite, although the impact of these changes on acute and prolonged EI remains unclear.